Answer:
Option B is the correct answer.
Explanation:
Thermal expansion
L = 1.2 meter
ΔT = 65 - 15 = 50°C
Thermal Expansion Coefficient for aluminum, α = 24 x 10⁻⁶/°C
We have change in length
New length = 1.2 + 1.44 x 10⁻³ = 1.2014 m
Option B is the correct answer.
Answer:
The coefficient of kinetic friction = 0.026
Explanation:
An 56 kg sled is being pulled across the snow, at constant speed,by a horizontal force of 15 N.
Here we have to note that the weight is pulled at a constant speed . This means that the net force acting on the weight is zero.
The external force acting on the body is in the forward direction and the friction acts in the backward direction.
Friction increases as the mass of the body increases.
Friction =
We now equate this to the external force of 15 N.
15 =
=
= 0.026
The coefficient of kinetic friction = 0.026