Answer:
C
Explanation:
An element is a pure substance that can not be broken down into anything simpler
A compound in also a pure substance held together in fixed proportion through chemical bonds
Answer:
remains the same
Explanation:
Momentum refers to the quantity of motion of a body. When any body of mass moves, it possess momentum. Numerically,
Momentum = mass x velocity
i.e. momentum is the product of the mass x velocity
Momentum of a body is always conserved.
In the context, the skateboard has certain momentum before Freddy lands on it. After Freddy lands, the momentum of skateboard remains the same, there is no change in the momentum.
This is because, here the momentum is conserved. After Freddy lands on the skateboard, the total mass on the skateboard increases and so the velocity decreases making the momentum same before the landing.
Answer:
7.68 m
Explanation:
Kinetic energy in ball = elastic energy in spring
KE = EE
½ mv² = ½ kx²
mv² = kx²
x = v √(m / k)
x = (38.5 m/s) √(20.5 kg / 515 N/m)
x = 7.68 m