Answer:
Explanation:
Given
length of window
time Frame for which rock can be seen is
Suppose h is height above which rock is dropped
Time taken to cover
so using equation of motion
where y=displacement
u=initial velocity
a=acceleration
t=time
time taken to travel h is
Subtract 1 and 2 we get
and from equation
so
and
so
substitute the value of in equation 2
Answer:
A
Explanation:
insects undergo Pupal life cycle
Answer:
It must return at the same velocity with which it was thrown or else there would be a preferred direction of motion leading to perpetual motion.
a = (v2 - v1) / t = (v2 - 0) / 2 = v2 / 2 for a falling object
v2 = 2 a = 2 sec * 9.8 m/sec^2 = 19.6 m/s
You can check with
H = V0 t - 1/2 g t^2 (V0 and g are in different directions)
H = 0
V0 = 1/2 g * 4 = 19.6 m/s
Infinite , is the correct answer for this question