Susan's 13.0 kg baby brother Paul sits on a mat. Susan pulls the mat across the floor using a rope that is angled 30∘ above the floor. The tension is a constant 29.0 N and the coefficient of friction is 0.170.

Question: Use work and energy to find Paul's speed after being pulled 2.60 m.

Paul's speed is 2.93m/s.

Explanation:

Let's call the tension on the rope and Paul's mass.  

The normal force on Paul equals his weight minus the upward vertical pull from the rope :

since

Therefore, the frictional force is

.

Thus, the net horizontal force on Paul is

where is the horizontal component of rope's tension and it is

therefore, the net force becomes

Now, when this horizontal net force pulls Paul by a horizontal distance , the work done is

and according to the work-kinetic energy theorem

which gives

solving for we get:

Finally, we put in numerical values

,

,

,

to get

Hence, when Paul is pulled by 2.60m, his speed becomes 2.93m/s.

iron would move it is magnetic there is a mag field around the current in the wire

answer///scientific method;