Physics
posted by Mina
A ball is throwing downward with an initial velocity of 10 m/sec. If the final velocity is 20 m/s, what is the time?

David Q/R
The equation you want is v = u + at, where u = initial velocity; v = final velocity; a = acceleration and t = time. v = 20. u = 10. a = 9.81 m/sec, though I'd guess from the numbers supplied that you may be expected to assume that a is approximately 10. You'll then be able to work it out from the above.
Respond to this Question
Similar Questions

Physics
A ball is thrown upward from the ground with an initial speed of 25 m/s; at the same instant, a ball dropped from rest from a building 15 m high. After how long will the balls be at the same height? 
College Physics
Two balls have masses 44 kg and 86 kg. The 44 kg ball has an initial velocity of 80 m/s (to the right) along a line joining the two balls and the 86 kg ball is at rest. The 86 kg ball has initial velocity of −24 m/s. The two … 
Physics
Two balls have masses 44 kg and 86 kg. The 44 kg ball has an initial velocity of 80 m/s (to the right) along a line joining the two balls and the 86 kg ball is at rest. The 86 kg ball has initial velocity of −24 m/s. The two … 
Physics
A ball rolling with initial velocity of 40m/s(W) undergoes an acceleration of 5.0m/s^2(N) for a period of 6.0seconds. (A) what is the final velocity of the ball? 
Physics
A ball rolling with initial velocity of 40m/s(W) undergoes an acceleration of 5.0m/s^2(N) for a period of 6.0seconds. (A) what is the final velocity of the ball? 
physics
Erica throws a ball out of a window with a horizontal speed of 3.8m/s. If the ball hits the ground 15m away, how high up is the window? 
Calculus
On planet Calculi, acceleration due to gravity is 20 ft/sec^2. A ball is thrown upward with an initial velocity of 40ft/sec from an initial height of 50. a) Write the equation for the height of the ball, s(t), at time t. b) Find the … 
Physical science b
The mass of ball A is 10kg and the mass of ball B is 5kg. If the initial velocity is set to 3 meters per sec for each ball, what is the final velocity of ball B if the final velocity of ball A is 2 meters per second? 
Physics
The mass of ball A is 10kg and the mass of ball B is 5kg. If the initial velocity is set to 3 meters per sec for each ball, what is the final velocity of ball B if the final velocity of ball A is 2 meters per second? 
Science
Plz help me plot on graph and also the solution. Q. When velocity is 20 m/s time is 0 and velocity 20 m/s time is 5 sec, velocity 10 m/sec time 7 sec, velocity 20 m/sec time 10 sec and velocity 0 time 15 sec. Calculate total distance …