A rock is thrown straight up with an initial velocity of 15m/s. ignore the effect of air resistance , how high will the rock rise ?
potential energy at top = kinetic energy at bottom
m g h = (1/2)m v^2
so
h = v^2/(2g)
= 225/(2*9.81)
about 11 meters
A rock is thrown downward with an initial velocity of 30 m/s. What is the velocity of the rock after it reaches 225 meters
A stone is thrown vertically upward from the ground with an initial velocity of 10 m/s .
A . What is the maximum height reached?
B.How long does the ball take to reach this maximum height ?
A ball is dropped from a bridge. It takes 4 s to reach the water below.
A. How high is the bridge above the water?
B. What is the velocity of the ball at the end of 1.5 seconds ?
A truck is travelling at 12 m/s and increases its speed to 28 m/s in 4 mintues .
What is its acceleration in m/s ^ 2 ?
A train brakes from 4 km/h to a stop over a distance of 200 m.
A. What is the acceleration in m/s ^ 2 of the train ?
B. How much time in seconds does it take the train to stop ?
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A car travels 80 m East and 60 m south in 10 min .
A.What is the displacement?
B.What distance has it travelled?
C.What is the speed of the car in m/s?
D. What is the car's velocity in m/s ?
How long does it take an airplane to take off if it needs to reach a speed on the ground of 250 km/h over a distance of 500 meters (assume the plane starts from rest ) ?
What is the acceleration in m/s ^2 of the airplane over the 500 meters ?