Answer:
The samples specific heat is 14.8 J/kg.K
Explanation:
Given that,
Weight = 28.4 N
Suppose, heat energy 
Temperature = 18°C
We need to calculate the samples specific heat
Using formula of specific heat


Where, m = mass
c = specific heat
= temperature
Q = heat
Put the value into the formula


Hence, The samples specific heat is 14.8 J/kg.K
Explanation:
You are given the initial velocity, the displacement, and the acceleration. You're looking for the final velocity. So you use the equation:
v² = v₀² + 2aΔy
When you solve for v, you take the square root. Your calculator will return a positive answer, but there are actually two possible answers: positive and negative.
v = ±√(v₀² + 2aΔy)
You must use the physical context of the problem. If we take up to be the positive direction, then v must be negative, since the projectile is moving down.
B.wrap more coils of wire around nail
this is the answer because the more coils the stronger the electrmagnet