Answer:
Explanation:
Given
height of grand canyon is 
Rock is dropped i.e. initial velocity is zero

Using Equation of motion

h=height
u=initial velocity
a=acceleration
t=time
here a=acceleration due to gravity


Answer:
An object on the moon would weigh the LEAST among these. So correct answer is B.
Explanation:
- Weight of an object on any place is given by:
W = Mass * Acceleration due to gravity(g)
- It means when masses of different objects those are in different places are same, the weight of those objects depends upon the 'g' of that particular place.
- As we know, acceleration due to gravity on surface of moon (g') is 6 times weaker than the acceleration on surface of earth (g), which is due to the large M/R^2 of the earth than the moon.
i.e. g' = g/6 so W' = W/6
- And in the space between the two, the object is weightless.
Answer:
Decrease
Explanation:
If you crawl to the rim the rotational speed will decrease. The law of conservation of angular momentum supports this answer. And it states that :
"When the net external torque acting on a system about a given axis is. zero , the total angular momentum of the system about that axis remains constant."
A person riding in an elevator subjected to a series of unbalanced forces depending on the direction the elevator is travelling.
Two forces are acting on the person; the force of gravity and the upward normal force from the elevator.
When the elevator is going upwards with acceleration a, the person feels heavier than his normal weight, due to the upward normal force being greater than the person's weight. N = mg + ma
When the elevator is moving downwards with acceleration a, the person feels lighter due to the downward normal force being less than the person's weight. N = mg - ma
However, when the elevator is moving up or down at constant velocity ie. acceleration a = 0, the person experience a normal force equal to weight. N = mg
When the elevator is moving downwards with acceleration a = g, the person experiences weightlessness. N = (mg - mg) = 0