Answer:
The change in gravitational potential energy of the climber-Earth system is 
Explanation:
From the question we are told that
The mass of the hiker is 
The time taken is 
The vertical elevation after time T is 
The change in gravitational potential is mathematically represented as

here g is the acceleration due to gravity with value
substituting values


Answer:
A
Explanation:
half life is the time taken for a radioactive isotopes to dissociate
Answer:
The force on one side of the plate is 3093529.3 N.
Explanation:
Given that,
Side of square plate = 9 m
Angle = 60°
Water weight density = 9800 N/m³
Length of small strip is


The area of strip is

We need to calculate the force on one side of the plate
Using formula of pressure


On integrating




Hence, The force on one side of the plate is 3093529.3 N.
As AL2006 correctly pointed out the formula is 1/2 kx^2. I was thinking of force and work is the integral of force over the distance applied. So now

and
Answer:
If you ring the doorbell and no one opens the door, you'll infer that no one is home rather than continuing to ring the doorbell to an empty house. Being able to understand this and look for another solution is another example of mental flexibility.
Explanation: