100 POINTS, NEED HELP ASAP

i just don’t get how to calculate all of these things

a) 57.4 N

b)

c) 1.97 s

d) 13.7 N

e) 68.6 N

Explanation:

The text and some of the data in the problem are missing, so I will make some assumptions on the problem and on some values.

a)

Here there are two girls that are applying each a horizontal force of 30 N through two ropes on the sled, at an angle of from each other.

Here we want to find the net tension force: therefore, we have to resolve the two forces along two perpendicular directions, and calculate the resultant.

Calling the two forces , and choosing the directions parallel and perpendicular to F1, we have:

- Along direction parallel to F1:

- Along the direction perpendicular to F1:

Therefore, the components of the net force are

Therefore, the net tension force is:

b)

The acceleration of the sled can be found by using Newton's second law of motion:

where

is the net force on the sled

m = 14 kg is the mass of the sled

a is the acceleration

The net force on the sled is given by the difference between the tension force T (forward) and the frictional force (backward), so we can write

where:

T = 57.4 N is the net tension

is the coefficient of friction

is the acceleration due to gravity

Solving for the acceleration,

c)

The motion of the sled is a uniformly accelerated motion, so we can use the following suvat equation:

where

u is the initial velocity

t is the time

a is the acceleration

s is the displacement

In this problem, we have:

u = 0 (I assume the sled starts from rest)

s = 6.0 m (distance covered by the sled)

(acceleration)

Solving for t, we find the time needed:

d)

The force of kinetic friction on a moving object on a flat surface is given by

where

is the coefficient of kinetic friction

m is the mass of the object

g is the acceleration due to gravity

For the sled in this problem, we have:

m = 14 kg

Therefore, the force of kinetic friction is:

e)

Here the sled stops on a slope with angle of

above the horizontal (I assumed this value since it is not given).

When the sled stops, there are two forces acting on it along the direction parallel to the slope:

- The component of the weight of the sled along the slope, down along the slope, of magnitude

- The force of static friction, , up along the slope

The sled at this moment is in equilbrium, so the two forces are balanced; so we can write:

And by substituting

We find:

Note: if some of the values that I have assumed are different, you can just plug in the correct numbers into the equation and find other results, but the procedure remains the same.

coil wire, increase current, put iron inside the coil