Answer:
Explanation:
Given that,
5J work is done by stretching a spring 
e = 19cm = 0.19m
Assuming the spring is ideal, then we can apply Hooke's law
F = kx
To calculate k, we can apply the Workdone by a spring formula
W=∫F.dx 
Since F=kx
W = ∫kx dx from x = 0 to x = 0.19
W = ½kx² from x = 0 to x = 0.19
W = ½k (0.19²-0²)
5 = ½k(0.0361-0)
5×2 = 0.0361k
Then, k = 10/0.0361
k = 277.008 N/m
The spring constant is 277.008N/m
Then, applying Hooke's law to find the applied force
F = kx
F = 277.008 × 0.19
F = 52.63 N
The applied force is 52.63N
 
        
             
        
        
        
Answer:

Explanation:
It is given that,
Depth of Death valley is 85 m below sea level, 
The summit of nearby Mt. Whitney has an elevation of 4420 m, 
Mass of the hiker, m = 65 kg
We need to find the change in potential energy. It is given by :



or

So, the change in potential energy of the hiker is  . Hence, this is the required solution.
. Hence, this is the required solution.
 
        
             
        
        
        
Answer:
25N
Explanation:
Assuming the lab is on earth:
w = mg = 2.5 (9.81) = 25N
 
        
             
        
        
        
Answer:
Distance = 30m
Displacement = 6m W
Explanation:
Given the following:
Movement 1 = 18m W
Movement 2 = 12m E
Diatance is a scalar quantity with only magnitude and no direction. That is, in Calculating the distance moved by the locomotive, the direction of travel or movement of the object is not considered. It only measures the total amount of movement made during the Time of motion. 
Therefore, total distance traveled equals :
Movement 1 + movement 2
18m + 12m = 30m
B) Displacement also measures the movement made by an object. However, Displacement is a vector quantity and therefore, considers both magnitude and direction of travel of the object. Therefore, it measures the overall change in position of the object from its starting position. 
Therefore, Displacement of the locomotive equals:
18m W - 12m E = 6m E
 
        
             
        
        
        
The force on the layer will be equivalent to the weight of water on it. This is given by:
F = mg; m is the mass of water and g is the acceleration due to gravity.