Answer:
power
Explanation:
it helps to do work without power we cant do any things
 
        
             
        
        
        
Answer:
Simple machine
Explanation:
It is a simple machine because the person wants to raise the load by an inclined plane. Simple machines perform work with the mechanical advantage offered by the machine itself, such as using a bar as Lever, lifting a load by means of a pulley. simple machines multiply or change direction a force. While Composite machines are the Union of several simple machines that perform a given job, examples of combined machines are found on bicycles, a washing machine, a car, and others.
 
        
                    
             
        
        
        
Answer:
   106.03 meters   
Explanation:
The height is given by the formula for motion under the influence of gravity.
   h = -4.9t^2 +162.7
Height is 0 when ...
   0 = -4.9t^2 +162.7
   4.9t^2 = 162.7
   t^2 = 162.7/4.9
   t = √(162.7/4.9)
The horizontal distance traveled in that time is ...
   (18.4 m/s)√(162.7/4.9) s ≈ 106.03 m
The object will strike the ground about 106.03 meters from the base of the cliff.
 
        
             
        
        
        
Answer:
The downwards acceleration is 3.53 m/s2. 
Explanation:
Let the true weight is m g. 
The reading of the balance, R = 0.64 mg 
Let the acceleration is a. 
As the apparent weight is less than the true weight so the elevator goes down wards with some acceleration.
Use Newton's second law 
m g - R = m a 
m g - 0.64 m g = m a 
0.36 g = a 
a = 3.53 m/s2
 
        
             
        
        
        
 Answer:
D) Fusion requires high temperatures and pressures, so how have they reduced the energy cost for it?
Explanation:
Fusion requires high temperatures and pressure for initiation of reaction . There is no chain reaction in it so there is no problem of controlling the problem . On the other hand , the reaction tends to stop as soon as temperature goes down due to heat getting dissipated . There is no problem of fuel as its fuel is deuterium which is present in nature in large amount . The question which is pertinent is that the cost involved in attaining so high temperature is very high so is it cost effective to produce energy by incurring so much of cost . Producing energy by using so much of energy in the beginning appears to be preposterous.