A ball is thrown horizontally with a speed of 20m/s from the top of a building 50m above the ground. How long does it take for the ball to strike the ground, and how far from the building does it strike?
First, we have:h=v_0 t +at²/2Since v_0=0, we have:50=1/2 at²at²=100t²=100/9.8=10.2t=3.193.19 secs x 20 m/s=63.89 meters
What is the velocity - time graph of a body thrown vertically up?
Velocity time graph of a body thrown vertically upwards can be made by easily once you understand the role of gravity in the motion that is occurring.In the case when the ball goes upwards the direction of velocity of the ball and the direction of acceleration of gravity are in the opposite directions so the velocity of ball will decrease until it reaches the top and stops momentarily. Eq-> v = u - gtThen from the peak position the ball will start to descend downwards due to the acceleration due to gravity that is g. Eq-> v = -gt(negative sign is due to the motion in downward direction)From both the equations you can see that the velocity and time are linearly proportional to each other which is the same as equation of a straight line. So this graph will be an straight line starting from velocity =u on the y axis and slope -g with time as the x axis.I am not able to upload the diagram here i don't know why but if you still have any confusion tell me about it.