Two stones are launched from the top of a tall building. One stone is thrown in a direction 15.0 ∘ above the horizontal with a speed of 20.0 m/s ; the other is thrown in a direction 15.0 ∘ below the horizontal with the same speed.
Which stone spends more time in the air? (Neglet air resistance)
a. The stone thrown upward spends more time in the air.
b. The stone thrown downward spends more time in the air.
c. Both stones spend the same amount of time in the air.

a. The stone thrown upward spends more time in the air.

Explanation:

The stone throw above the horizontal 15° with the same speed as the stone thrown below the horizontal by 15° will remain in the air for a longer time because its vertical component act in the upward direction due to which it first ascends in height and then falls down whereas the stone projected downwards from horizontal will have an additional component of velocity acting in the downward direction due to which it reaches the ground faster.

dec 23, 2016 - a load of bricks weighing 680 n a distance of 10 m across a parking lot. if if the worker pushes the cart with a constant force of 209 n, what work= force x distance = 220 n x 10 m = 2200 n.m = 2200 j i don't know where the person got it from, but the initial part, work= force x distance me.