Answer: Fr = 26.53 N
Explanation: The constant force exerted on the block by the surface is the frictional force.
This frictional force is as a result of interaction between the body and the surface.
According to newton's second law of motion,
F - Fr = ma
F=applied force
Fr = magnitude of frictional force
m = mass of object = 12kg
a = acceleration of object = 3.2m/s²
The applied force (F= 75 N) is inclined at an angle of 30° to the horizontal thus making it have 2 components of forces given below
Fx = 75 * cos 30 = 64.95 N (horizontal component)
Fy = 75 * sin 30 = 37.5 N ( vertical motion)
The body moves across the surface, hence the horizontal component of force is responsible for motion.
F = 64.95 N
By substituting the parameters, we have that
64.96 - Fr = 12 * 3.2
64.96 - Fr = 38.4
Fr = 64.96 - 38.4
Fr = 26.53 N
I think it's B for electrons
<span>Nonliving things also have unlimited duration of existence. While living things die and decompose, nonliving things such as rocks, mountains, air and water have existed for millions of years. They may grow, but they do so only by accretion, which is the process of growth by accumulating added layers of matter.</span>
Measuring mass with a balance
Answer:static, sliding, rolling,
Explanation: