Answer:
The change is momentum is given by ∆p=p(inital) - p(final) =4-2=2 kg.m/s
Explanation:
momentum is the product of mass and velocity (speed)
So it's initial momentum would be:
p=mv=(1)(4)=4 kg.m/s
It's final momentum is given by:
p=mv=(1)(2)=2 kg.m/s
Answer:
Force = 3.333 Newton
Explanation:
Given the following data;
Change in momentum = 10 Kgm/s
Time = 3 seconds
To find the force acting on it;
In Physics, the change in momentum of a physical object is equal to the impulse experienced by the physical object.
Mathematically, it is given by the formula;
Force * time = mass * change in velocity
Impulse = force * time
Substituting into the formula, we have;
10 = force * 3
Force = 10/3
Force = 3.333 Newton
Answer:

Explanation:
Given: The latent heat of fusion for Aluminum is 
mass to be malted m = 0.75 Kg
Energy require to melt E = mL

Therefore, energy required to melt 0.75 Kg aluminum

The most probable reason why the magnets won't stick on the refrigerator is that the body of the refrigerator and the magnets have like poles. If both have negative or both have positive poles facing each other, they will repel. In principle, magnets are attracted to opposite poles and like poles repel.