• CHALLENGE You need to move a 105-kg sofa to a different location in the room. It takes a 403-N force to start the sofa moving. What is the coefficient of static friction
between the sofa and the carpet?

μ = 0.391

Explanation:

The friction force is defined as the product of the coefficient of friction by the normal force. In this way, we have the following equation.

F = μ*N

Where:

F = friction force = 403 [N]

μ = static coefficient

N = Normal force [N]

And the normal force of a body lying on a horizontal surface can be calculated by means of the product of mass by gravitational acceleration.

Now we can clear the  static coefficient

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.

answer: b.

explanation: