Answer:
<em>a. The rock takes 2.02 seconds to hit the ground</em>
<em>b. The rock lands at 20,2 m from the base of the cliff</em>
Explanation:
Horizontal motion occurs when an object is thrown horizontally with an initial speed v from a height h above the ground. When it happens, the object moves through a curved path determined by gravity until it hits the ground.
The time taken by the object to hit the ground is calculated by:

The range is defined as the maximum horizontal distance traveled by the object and it can be calculated as follows:

The man is standing on the edge of the h=20 m cliff and throws a rock with a horizontal speed of v=10 m/s.
a,
The time taken by the rock to reach the ground is:


t = 2.02 s
The rock takes 2.02 seconds to hit the ground
b.
The range is calculated now:

d = 20.2 m
The rock lands at 20,2 m from the base of the cliff
We know that velocity is equal to the total displacement of an object over time.

Deriving from that equation, we can say that:

Okay, so here it goes:

The bicycle took 25.02 seconds to displace at 58.3 meters.
Answer:
a.
b.
Explanation:
We are given that




a.We have to find the angle


b. We have to find the speed 
According to law of conservation of momentum



Answer: 0.067 s
Explanation:s = Ut + 1/2at^2
0.6 = 9t + 0.5 *10 *t^2
Where a = g =10m/s/s
Solving the quadratic equation
5t^2 + 9t - 0.6=0,
t= 0.067 s and - 1.7 s
Of which 0.067 s is a valid time