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Course: High school physics > Unit 1

Lesson 7: Objects in freefall
Science
High school physics
One-dimensional motion
Objects in freefall
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Solving freefall problems using kinematic formulas

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Problem

A squirrel drops an acorn onto the head of an unsuspecting dog. The acorn falls 4.0m before it lands on the dog. We can ignore air resistance.
How many seconds did the acorn fall?
Round the answer to two significant digits.
Answer using a coordinate system where upward is positive.
  • Your answer should be
  • an exact decimal, like 0.75
s