W=20 e(-kt)
A. Rearranging gives k= -(ln(w/20)/t
Substituting w= 10 and solving gives k=0.014
B. Using W=20e(-kt). After 0 hours, W=20. After 24 hours, W=14.29g. After 1 week (24x7=168h) W=1.9g
C. Rearranging gives t=-(ln(10/20)/k. Substituting w=1 and solving gives t=214 hours.
D. Differentiating gives dW/ dt = -20ke(-kt). Solving for t=100 gives dW/dt = 0.07g/h. Solving for t=1000 gives 0.0000002g/h
E. dW/dt = -20ke(-kt). But W=20e(-kt) so dW/dt = -kW
Answer: 376.32 J
Explanation: Gravitational potential energy is the energy possessed by a body by virtue of its position.

m= mass of the body = 48 kg
g= acceleration due to gravity= ]
h= height of body= 0.8 m

Answer:

Explanation:
The minimum height of a space shuttle from the surface of the earth is 304 kilometers.
So according to this data we calculate the value to g at that height.
We have the formula:

where:
g' = the acceleration due to gravity at the given height 'h' above the earth
R = radius of the earth
g = the acceleration due to gravity at the surface of the earth
Now, using eq. (1)

