Answer: F = 33.6 N
Explanation: work = force · distance or W = F·s
Force F = W/s = 504 J/15 m
Answer:
T = 764.41 N
Explanation:
In this case the tension of the string is determined by the centripetal force. The formula to calculate the centripetal force is given by:
(1)
m: mass object = 2.3 kg
r: radius of the circular orbit = 0.034 m
v: tangential speed of the object
However, it is necessary to calculate the velocity v first. To find v you use the formula for the kinetic energy:

You have the value of the kinetic energy (13.0 J), then, you replace the values of K and m, and solve for v^2:

you replace this value of v in the equation (1). Also, you replace the values of r and m:

hence, the tension in the string must be T = Fc = 764.41 N
Acceleration=(speed end - speed start)/ time
Data:
speed end=4 m/s
speed start=0 m/s
time=2.5 s
acceleration=(4 m/s - 0 m/s)/2.5 s=1.6 m/s²
Answer: the acceleration would be 1.6 m/s²