https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-force-laws-of-motion/in-in-newtons-first-law/v/newtons-first-law-intro-forces-causes-motion 2021-04-06T14:32:18Z Newton's first law intro (forces causes motion?) Do forces really cause motion? Let's find out with examples. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/Lc89Q7sESKwduREfm_KvYzGTK9rHwLqmG6AjR0djm0su9mqm4BmFRD_BgLvyCD6iwhG6DaJuZswCCgQkcjyrKCFH Newton's first law intro (forces causes motion?) Do forces really cause motion? Let's find out with examples. https://cdn.kastatic.org/ka-youtube-converted/nSOcHFahe2Q.mp4/nSOcHFahe2Q.mp4 633 Newton's Laws of motion https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-force-laws-of-motion/in-in-newtons-first-law/v/balanced-unbalanced-forces 2021-04-06T14:32:18Z Balanced & unbalanced forces Lets use real life examples and study balanced and unbalanced forces. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/xTvWFpvFRN-V_KvCH9_FQ6r7udCAPRVPebKj8aXLCPMPD8det6BkD7uoh-Q26vzAzjZYKyV04PxriMMLGuscm1c Balanced & unbalanced forces Lets use real life examples and study balanced and unbalanced forces. https://cdn.kastatic.org/ka-youtube-converted/CGdC5eZprW4.mp4/CGdC5eZprW4.mp4 678 Newton's Laws of motion https://www.khanacademy.org/science/physics/forces-newtons-laws/newtons-laws-of-motion/v/unbalanced-forces-and-motion 2022-11-16T04:22:43.7414897Z Unbalanced forces and motion Use your knowledge of balanced and unbalanced forces to evaluate four statements related to the behavior of objects when acted on by forces and to determine whether each statement is true or false. Sal Khan video https://cdn.kastatic.org/googleusercontent/GLJ00BQ1bzpb6J8pZ6A6xtW3H6-SYnPYYsoumt8PyiXtHru9Fv_pJQapJmTj0Yyqr0MQIKPdwQOOgie7THbx2dwE Unbalanced forces and motion Use your knowledge of balanced and unbalanced forces to evaluate four statements related to the behavior of objects when acted on by forces and to determine whether each statement is true or false. https://cdn.kastatic.org/ka-youtube-converted/IgYUR7aFY-c.mp4/IgYUR7aFY-c.mp4 397 Newton's Laws of motion https://www.khanacademy.org/science/physics/forces-newtons-laws/newtons-laws-of-motion/v/newton-s-1st-law-of-motion 2023-04-30T21:01:15.828786566Z Newton's first law of motion introduction Newton's first law states that objects move with constant velocity unless acted upon by an unbalanced force. If the net force on an object is zero, it will remain at rest (if already at rest) or continue moving with constant speed and direction. A force is not required to keep an object in motion unless an opposing force is present. Sal Khan video https://cdn.kastatic.org/googleusercontent/dZh-Iil8Ln_LEd2NyCwA9idfqSMo4gpOOvMUiEvSTlV9OYVV7PrkEZj9Hcs4X9c55AZcUnYJR4P3s7SznPSIhpEw Newton's first law of motion introduction Newton's first law states that objects move with constant velocity unless acted upon by an unbalanced force. If the net force on an object is zero, it will remain at rest (if already at rest) or continue moving with constant speed and direction. A force is not required to keep an object in motion unless an opposing force is present. https://cdn.kastatic.org/ka-youtube-converted/5-ZFOhHQS68.mp4/5-ZFOhHQS68.mp4 326 Newton's Laws of motion https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-force-laws-of-motion/in-in-newtons-first-law/v/newton-s-first-law-of-motion 2023-09-10T17:11:17.624018169Z Newton's first law of motion Newton's First Law of Motion, also known as the Law of Inertia, states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This law, originally formulated by Galileo, is fundamental to understanding motion and forces. Sal Khan video https://cdn.kastatic.org/googleusercontent/fmS9hIt1iuTvGIeiQlC-CGjahm0tY7oWSnCxEJtz4bIiz2VWwYKYwJ1GkLJNK8vkSVnIEBva5fjjJ84GF4W-LEe- Newton's first law of motion Newton's First Law of Motion, also known as the Law of Inertia, states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This law, originally formulated by Galileo, is fundamental to understanding motion and forces. https://cdn.kastatic.org/ka-youtube-converted/CQYELiTtUs8.mp4/CQYELiTtUs8.mp4 572 Newton's Laws of motion https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class-11-newtons-first-law-mass-and-inertia/v/newton-s-first-law-of-motion-concepts 2023-04-30T21:01:15.828786566Z Applying Newton's first law of motion Newton's first law quiz 1. If the net force on an object is zero, its velocity won't change. (True) 2. An unbalanced force on an object will always impact the object's speed. (False) 3. Moving objects come to rest in everyday life because of unbalanced forces. (True) 4. An unbalanced force on an object will always change the object's direction. (False) Sal Khan video https://cdn.kastatic.org/googleusercontent/LHxurZ01Zp0KtWeR2uYhrqzFkmPLZJXtrqcPtasuobaziWs2gdy2piHfNwoAtkZ6HvzlYQ7HljL6nYkLiJUea7DT Applying Newton's first law of motion Newton's first law quiz 1. If the net force on an object is zero, its velocity won't change. (True) 2. An unbalanced force on an object will always impact the object's speed. (False) 3. Moving objects come to rest in everyday life because of unbalanced forces. (True) 4. An unbalanced force on an object will always change the object's direction. (False) https://cdn.kastatic.org/ka-youtube-converted/D1NubiWCpQg.mp4/D1NubiWCpQg.mp4 434 Newton's Laws of motion https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class-11-newtons-first-law-mass-and-inertia/a/what-is-newtons-first-law 2025-03-07T16:50:49.734868403Z What is Newton's first law? Also called the law of inertia, this is the most important thing to realize about motion. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class-11-newtons-first-law-mass-and-inertia/a/what-is-weight 2025-02-28T00:12:11.735240474Z What is weight? Weight is another word for the force of gravity. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class-11-newtons-first-law-mass-and-inertia/a/newtons-first-law-review 2021-04-29T07:52:11Z Newton's first law review Review the key concepts, equations, and skills for Newton's first law of motion, including the difference between mass and weight article https://www.khanacademy.org/science/bridge-course-class-11th-physics/x4c0d503cda725c32:laws-of-motion/x4c0d503cda725c32:newton-s-first-law-of-motion/e/first-law-of-motion 2025-04-09T10:12:02.040424533Z First law of motion Let's solve some questions vibhor exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class-11-newtons-first-law-mass-and-inertia/e/newtons-first-law-exercises-ap1 2026-03-25T13:20:47.939559562Z Net force and acceleration exercise Practice using Newton's first law to make conclusions about an object's acceleration or the forces on the object.  April Russell exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class-11-newtons-first-law-mass-and-inertia/e/newton-s-first-law-exercise 2022-11-27T23:01:15.143242814Z Analyzing motion using Newton's laws Let's solve some problems which will help us clear some common misconceptions regarding Newton's first law and its applications. Aakash Bagga exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class11-newtons-second-law/v/newton-s-second-law-of-motion 2023-04-30T21:01:15.828786566Z Newton's second law of motion Newton's second law of motion states that F = ma, or net force is equal to mass times acceleration. A larger net force acting on an object causes a larger acceleration, and objects with larger mass require more force to accelerate. Both the net force acting on an object and the object's mass determine how the object will accelerate. Sal Khan video https://cdn.kastatic.org/googleusercontent/APQcdQoh57rMTIj4pO6TbuiqvHQANnm89JTjbSFLIR_NtjMRinQepUzzyhOjr03EGiUXKZ9BVyqhV7sjCXSC1zM Newton's second law of motion Newton's second law of motion states that F = ma, or net force is equal to mass times acceleration. A larger net force acting on an object causes a larger acceleration, and objects with larger mass require more force to accelerate. Both the net force acting on an object and the object's mass determine how the object will accelerate. https://cdn.kastatic.org/ka-youtube-converted/ou9YMWlJgkE.mp4/ou9YMWlJgkE.mp4 434 Newton's Laws of motion https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:newtons-first-and-second-laws/v/newtons_second_law_calculations 2024-07-01T11:54:52.194339821Z Newton's second law calculations Newton's second law can be used to calculate the acceleration that an object will experience, if the net force acting on the object and its mass are known. The law can also be used to determine the net force required to produce a certain acceleration for a known mass. Remember that the force term in Newton's second law refers to the net force on the object. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/2c25a321-d139-4a9b-b26c-a7f9a5ec0251_1280_720_base.png Newton's second law calculations Newton's second law can be used to calculate the acceleration that an object will experience, if the net force acting on the object and its mass are known. The law can also be used to determine the net force required to produce a certain acceleration for a known mass. Remember that the force term in Newton's second law refers to the net force on the object. https://cdn.kastatic.org/ka-youtube-converted/O5G4uHe-qc4.mp4/O5G4uHe-qc4.mp4 595 Newton's Laws of motion https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-force-laws-of-motion/in-in-newtons-second-law-inertia/v/finding-force-newtons-second-law-solved-example 2021-04-06T14:32:18Z Finding force - Newton's second law (Solved example) Let's solve some examples of Newton's second law of motion. Given various details of motion, we will see how to calculate the force on a body (using the second law of motion formula F = ma). Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/V51jg6ZellfsctgLveVeoTvz9kNz2UHNawAW5ZLgJtASbc9ItnSJCFc9T4Km88tWCF5jaC-va7N7P6zo5TsG6aHeag Finding force - Newton's second law (Solved example) Let's solve some examples of Newton's second law of motion. Given various details of motion, we will see how to calculate the force on a body (using the second law of motion formula F = ma). https://cdn.kastatic.org/ka-youtube-converted/A-0EWBCxikg.mp4/A-0EWBCxikg.mp4 712 Newton's Laws of motion https://www.khanacademy.org/science/physics/forces-newtons-laws/newtons-laws-of-motion/v/more-on-newtons-second-law 2023-04-30T21:01:15.828786566Z More on Newton's second law Newton's second law can be used to solve two-dimensional motion problems. If any force vectors are acting at an angle, they can be broken into their horizontal and vertical components using trigonometry. Then, the net force in each dimension and the object's mass are entered into Newton's second law (F=ma) to determine the resulting acceleration in each dimension. David SantoPietro video https://cdn.kastatic.org/googleusercontent/5fUd18SOA-lwzZTeppReyoUSiHwDF6qppYcGYqvjWSBfaISCXI-uig332-UrrQ-J03NL8mzMqMrjRx1OUdCcU9Ur More on Newton's second law Newton's second law can be used to solve two-dimensional motion problems. If any force vectors are acting at an angle, they can be broken into their horizontal and vertical components using trigonometry. Then, the net force in each dimension and the object's mass are entered into Newton's second law (F=ma) to determine the resulting acceleration in each dimension. https://cdn.kastatic.org/ka-youtube-converted/24vtg9Ehr0Q.mp4/24vtg9Ehr0Q.mp4 963 Newton's Laws of motion https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:newtons-first-and-second-laws/a/what-is-newtons-second-law 2025-11-02T20:30:38.934534269Z Newton's first and second laws Learn how to predict the translational motion of objects using Newton's first and second laws. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class11-newtons-second-law/a/newtons-second-law 2024-06-17T03:54:13.682210978Z Newton's second law review Review the key concepts, equations, and skills for Newton's second law of motion, including how to analyze motion in the x- and y-directions independently. article https://www.khanacademy.org/science/ap-college-physics-1/xf557a762645cccc5:force-and-translational-dynamics/xf557a762645cccc5:forces-and-acceleration/e/newton-s-second-law 2026-04-07T22:59:30.107127435Z Newton's second law Practice applying Newton's second law to symbolically solve for mass, acceleration, and force magnitude.  Sean Boston exercise https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:newtons-first-and-second-laws/e/apply-newton-s-second-law-calculations 2026-01-23T16:30:41.215368476Z Apply: Newton's second law calculations Apply your knowledge of Newton's second law calculations in this set of free practice questions. Emily Cizmas exercise https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:newtons-first-and-second-laws/e/apply-newton-s-second-law 2026-01-23T20:00:36.154127952Z Apply: Newton's first and second laws Apply your knowledge of Newton's second law in this set of free practice questions. Emily Cizmas exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class11-newtons-third-law/v/newton-s-third-law-of-motion 2023-04-30T21:01:15.828786566Z Newton's third law of motion Newton's third law states that for every action there is an equal and opposite reaction. The "action" and "reaction" refer to forces; if Object A exerts a force on Object B, then Object B exerts an equal amount of force on Object A in the opposite direction. Examples include pushing an object, stepping on the ground, and rockets. Sal Khan video https://cdn.kastatic.org/googleusercontent/Z6-bO4W7OJb9wSIOyD061O5-5nPNlcTxduwQL99ftRoES7Z8Ae2JbDHZ0y3Eb7BkGvedAzae1Y0PQJyx7OS-r9c Newton's third law of motion Newton's third law states that for every action there is an equal and opposite reaction. The "action" and "reaction" refer to forces; if Object A exerts a force on Object B, then Object B exerts an equal amount of force on Object A in the opposite direction. Examples include pushing an object, stepping on the ground, and rockets. https://cdn.kastatic.org/ka-youtube-converted/By-ggTfeuJU.mp4/By-ggTfeuJU.mp4 480 Newton's Laws of motion https://www.khanacademy.org/science/physics/forces-newtons-laws/newtons-laws-of-motion/v/more-on-newtons-third-law 2023-04-30T21:01:15.828786566Z More on Newton's third law Newton's third law states that objects exert equal and opposite forces on each other in every interaction. However, these forces do not cancel out because they act on two different objects. The magnitudes of the forces on both objects will be always be equal, but their resulting accelerations will not be equal if the objects have different masses. David SantoPietro video https://cdn.kastatic.org/googleusercontent/6U1crxkR7IThstBtIjjX6GEQ1kN7KtxHqaK4pF4B3NaemzOrPv1LoeWFLASk15ytuflAJCeTjcEkOubGICF4jzrbsA More on Newton's third law Newton's third law states that objects exert equal and opposite forces on each other in every interaction. However, these forces do not cancel out because they act on two different objects. The magnitudes of the forces on both objects will be always be equal, but their resulting accelerations will not be equal if the objects have different masses. https://cdn.kastatic.org/ka-youtube-converted/VfpKzwrhmqQ.mp4/VfpKzwrhmqQ.mp4 786 Newton's Laws of motion https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/a/forces-and-newtons-third-law 2025-07-29T20:26:13.489588275Z Forces and Newton's third law Forces always exist in pairs. Explore how the forces in these pairs compare to each other, and why they don't balance each other. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class11-newtons-third-law/a/newtons-third-law-ap1 2021-04-29T07:55:51Z Newton's third law review Review the key concepts and skills for Newton's third law of motion, including how to identify action-reaction pairs. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class11-newtons-third-law/e/newton-s-third-law 2026-03-25T13:20:47.939559562Z Identifying equal and opposite forces Practice identifying the correct reaction to an action using Newton's third law.  Sean Boston exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-laws-of-motion/in-in-class11-newtons-third-law/e/newtons-third-law 2026-03-25T13:20:47.939559562Z Newton's third law of motion Conceptual question testing understanding of Newton's Third Law of Motion Sal Khan exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/apply-forces-and-newton-s-third-law 2025-12-21T20:47:51.596633051Z Apply: forces and Newton's third law Apply your knowledge of forces and Newton's third law in this set of free, standards-aligned practice questions. Molly Sauder exercise