Answer:
The answer is given below
Explanation:
u is the initial velocity, v is the final velocity. Given that:

a)
The final velocity of cart 1 after collision is given as:

The final velocity of cart 2 after collision is given as:

b) Using the law of conservation of energy:

Answer:

Explanation:
information we know:
Total force: 
Weight: 
distance: 
vertical component of the force: 
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In this case we need the formulas to calculate the components of the force (because to calculate the work we need the horizontal component of the force).
horizontal component: 
vertical component: 
but from the given information we know that 
so, equation these two
and 

and we know the force
, thus:

now we clear for 

the angle to the horizontal is 15.466°, with this information we can calculate the horizontal component of the force:


whith this horizontal component we calculate the work to move the crate a distance of 4 m:

the work done is W=173.48J
Impulse = change in momentum
The car's momentum was (mass) x (speed)
Momentum = (2400 kg) x (20 m/s)
Momentum = 48,000 km-m/s
To completely stop the car, the impulse = -48,000 km-m/s .
Answer:2. The number of miles driven and the amount of gas used.
Explanation:
Answer:
The amount of work we could expect to get out of the system per second = 28,000J/s
Explanation:
Given the power supplied to the system as 28kW;
Energy = power / time
At very best, the amount of work we could expect to get out of the system per second = 28,000 W / 1 second = 28,000J/s
Therefore, for a a furnace which supplies 28kW of thermal power at 300C to an engine and exhausts waste energy at 20C.
At the very best, the amount of work we could expect to get out of the system per second = 28,000J/s