414,795 views
42 votes
42 votes
A ball is rolled horizontally off a table with an initial speed of 0.24 m/s. A stopwatch measures the ball's trajectory time from table to the floor to be 0.30 s. What is the height of the table? (g = 9.8 m/s2 and air resistance is negligible)

User Geoff Reedy
by
2.5k points

1 Answer

11 votes
11 votes

Answer:

Step-by-step explanation:

Comment

This is a good question to know how to do. You don't use the 0.24 m/s because that is a horizontal speed. Nothing opposes it. So the question becomes, what is happening vertically. You treat this question as though you just dropped the ball.

Givens

v0 = 0 The ball has no vertical speed to start with

a = 9.8 m/s^2

t = 0.30 seconds

Formula

d = vo*t + 1/2*a*t^2 Substitute the givens into the formula

Solution

d = 0*t + 1/2 * 9.8 * 0.3^2

d = 0.88 meters rounded to two palaces.

User Jonny Lin
by
3.4k points