Answer:

Explanation:
The centripetal force is given by:

Here m is the body's mass in which the force is acting and
is the centripetal acceleration:

Here v is the speed of the body and r its radius. The speed is given by:

Replacing (3) in (2):

Replacing (4) in (1) and solving for f:

Answer:
The center of mass of the two-block system is staying the same and it can be explained with the help of linear momentum equation.
Explanation:
The center of mass of the two-block system is staying the same and it can be explained with the help of linear momentum equation.
Equation:
P=mv
This equation holds if no external force is acting on the system it means the momentum of the system is constant.
In our case, there is no external force which means the total momentum of system is constant:
P=constant
Total mass of system is also constant:
m=constant
It means the velocity of the system is constant (from above equation) thus center of mass of the two-block system is staying the same
Explanation:
(a) Displacement of an object is the shortest path covered by it.
In this problem, a student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag. She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school.
0.4 miles = 0.64 km
displacement = 0.7-0.3+0.64 = 1.04 km
(b) Average velocity = total displacement/total time
t = 15 min = 0.25 hour

Hence, this is the required solution.
Answer:
Potential Difference = 14 V
Explanation:
We are told that when the capacitor plates are charged to a certain voltage, then we have;
ΔV = 14 volts
Now, the battery is disconnected, so here we have the potential difference between the plates to be given by the formula;
ΔV = Q/C
Now, the charge is conserved on the plates and the capacitance is constant, therefore in this case, the potential difference will remain the same.
Thus;
Potential Difference = 14 V