Question 1
A stone is thrown vertically upwards with a initial speed of 10 m/s from the edge of the roof of the house of Height H=20 m
a) how long does it takes for the stone to hit the ground
b) At what velocity it will hit the ground
Answers
Answer:
Answer: The stone will reach the ground in 5 seconds after being thrown upwards from the tower.
Solution. 50km/h,50km/h.
Answer:
a) It will take 2.23 seconds to the stone to hit the ground.
b) The velocity with which it will hit the ground is 22.3 m/s.
Explanation:
Given :
Initial Velocity (u) = 10 m/s
Height (H) = 20 m
Now, finding time to reach maximum limit,
v = u + at
0 = 10 +( -10) t
t = 1 sec
Now, finding the distance from roof to maximum limit :
s = ut + (1/2) at^2
s = 10 × 1 + (1/2)(-10) ×1
s = 5 m
Now, finding time to reach the ground from the maximum height :
s = ut + (1/2) at ^2
25 = 0 + (1/2) ×(10) t^2
25 = 5 t^2
5 = t^2
t = √5 sec = 2.23 sec
Hence, it will take 2.23 seconds for the stone to hit the ground.
Now, Calculating velocity with which it reaches the ground.
v = u + at
v = 0 + 10 × 2.23
v = 22.3m/s
Hence, the final answer is a) 2.23 seconds b) 22.3 m/s
#SPJ2