What is the maximum acceleration the belt can have without the crate slipping? express your answer using two significant figures?

To prevent the crate from slipping, the maximum force that the belt can exert on the crate must be equal to the static friction force.

Ff = 0.5 * 16 * 9.8 = 78.4 N

a = 4.9 m/s^2

If acceleration of the belt exceeds the value determined in the previous question, what is the acceleration of the crate?

In this situation, the kinetic friction force is causing the crate to decelerate. So the net force on the crate is 78.4 N minus the kinetic friction force.

Ff = 0.28 * 16 * 9.8 = 43.904 N

Net force = 78.4 – 43.904 = 34.496 N

To determine the acceleration, divide by the mass of the crate.

a = 34.496 ÷ 16 = 2.156 m/s^2

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

auroras are generated by charged solar particles hitting molecules in earth's atmosphere. this usually happens in high latitudes, because our planet’s magnetic field tends to funnel these particles toward the poles. that’s why it can be experienced in northern ohio.