Answer:
5 W
Explanation:
The formula of the power is: 
● P = W/t 
W is the work and t is the time needed to do it(in seconds) 
Let's calculate first the work that the force exerced:
W = Vector F . Vector d 
D is the distance ( here 400 cm wich is 4 m)
Make a representation to see how are the vectors F and V.(picture below)
The vector F and d are colinear since Den is pushing the desk on the ground.
● W = 4 × 10 = 40 J 
J is Joule 
■■■■■■■■■■■■■■■■■■■■■■■■■■
● P = W / t 
● P = 40/ 8
● P = 5 W 
 
        
             
        
        
        
Answer:
v= 4 m/s
Explanation:
Momenutm is, by definition, the product of mass and velocity.

Let's replace what we know and solve for whatever's left

 
        
             
        
        
        
Answer:
K = 1800 kJ
Explanation:
Given that,
The speed of the object, v = 30 m/s
Mass of the object, m = 4000 kg
We need to find the kinetic energy of the object. The formula for the kinetic energy is given by :

So, the required kinetic energy is equal to 1800 kJ.
 
        
             
        
        
        
Answer:
ACCELERATING OR DECELERATING
Explanation:
I'M NOT SURE 
 
        
             
        
        
        
Answer:
In physics, power is the amount of energy transferred or converted per unit time. In the ... Power (physics) ... Angular acceleration / displacement / frequency / velocity. show. Scientists ... Hence the formula is valid for any general situation. ... because they define the maximum performance of a device in terms of velocity ratios
Explanation: