Answer:
Fc = 89.67N
Explanation:
Since the rope is unstretchable, the total length will always be 34m.
From the attached diagram, you can see that we can calculate the new separation distance from the tree and the stucked car H as follows:
L1+L2=34m
Replacing this value in the previous equation:
Solving for H:

We can now, calculate the angle between L1 and the 2m segment:

If we make a sum of forces in the midpoint of the rope we get:
where T is the tension on the rope and F is the exerted force of 87N.
Solving for T, we get the tension on the rope which is equal to the force exerted on the car:

Only first is kinetic.
So 2-3-4 are not
Since the force acting is two dimensional, resolve it along the horizontal surface and perpendicular to the surface by using *resolution of vectors*
Answer:
Explanation:
Radius of circular path of coin R = 12.5 x 10⁻²,
coefficient of static friction μs = .33
In order that the coin rotates in circular path , it requires centripetal force which is provided by friction. As speed of rotation increases , force of friction also increases to provide it required centripetal force. When the speed of rotation becomes too high so that frictional force can not compensate the increase in centripetal force then coin will start slipping or it starts moving with respect to turntable.
b ) At this point of time
centripetal force = limiting force of friction
mω² R = μs mg , m is mass of the coin , ω is angular velocity ,
ω² R = μs g
ω² x 12.5 x 10⁻², = .33 x 9.8
ω² = .33 x 9.8 / 12.5 x 10⁻²,
= 25.87
ω = 5.08 rad / s
2π / T = 5.08
T = 2π / 5.08
= 1.23 s .