Answer:
They´re the same.
Explanation:
Someone deleted my answer. And my brainly is gone..
Have a good night ma´am/sir.
Be safe!
As we know that in order to melt the copper we need to take the temperature of copper to its melting point
So here heat required to raise the temperature of copper is given as

We know that
melting temperature of copper = 1085 degree C
Specific heat capacity of copper = 385 J/kg C
now we have



now in order to melt the copper we know the heat required is

here we know that
L = 205 kJ/kg
now from above formula


now total heat required will be


As we know that

now we have

The answer is b.) the momentum before the collision is greater than the momentum after the collision
Answer:
Energy is essentially work done by an object or on object.
From,
W = Fd
It's directly proportional to mass.
from,
K. E = 1/2mv²
Energy is directly proportional to mass.
P. E = mgh
Energy is directly proportional to mass.
H = mc∆T
Energy is directly proportional to mass.
Thus increasing mass will increase the energy also imparted on another object since all the above eqns show that relationship.
And for 2 moving bodies
K.Ei = K.Ef(energy conservation)
m1u²1 + m2u²2 = m1v²1 + m2v²2
The relationship is the same that the greater mass the greater the impact.
72km/hr = 72000m/3600seconds(we convert km/hr to m/s
= 20m/s
Velocity= 20m/s
In 4seconds,distance covered=20x4= 80m
Therefore,an accident occurs because in 4seconds, the car would have moved past 20m