Answer:
Magnitude of static friction force is 70 sin40° = 44.99 N.
No, it is not necessary that it is maximum static friction.
Normal force is equal to 70 cos40° = 53.62 N.
Explanation:
We apply newton law of moton equation along the plane and perpendicular to plane;
Along the plane,
70 sin 40° = ---------------(1)
70 cos 40° = N --------------(2)
= μN -----------------(3)
So, it depends on the value of μ that the friction is maximum or not .
Answer:
Explanation:
According to Coulomb's law, the magnitude of the electric force between two point charges is directly proportional to the product of the magnitude of both charges and inversely proportional to the square of the distance that separates them:
Here k is the Coulomb constant. In this case, we have ,
and
. Replacing the values:
The negative sign indicates that it is an attractive force. So, the magnitude of the electric force is:
Answer:
B. 2 meters.
Explanation:
To rotate the capstan a certain amount of torque is required, and if each sailor applies a force at a distance
from the center, then for two sailors the total torque will be
;
therefore, for one sailor to apply the same torque it must be that the torque he applies must be equal to the torque that the two sailors applied:
which gives
.
and since ,
which is choice B.