<span>7.7 m/s
First, determine the acceleration you subject the sled to. You have a mass of 15 kg being subjected to a force of 180 N, so
180 N / 15 kg = 180 (kg m)/s^2 / 15 kg = 12 m/s^2
Now determine how long you pushed it. For constant acceleration the equation is
d = 0.5 A T^2
Substitute the known values getting,
2.5 m = 0.5 12 m/s^2 T^2
2.5 m = 6 m/s^2 T^2
Solve for T
2.5 m = 6 m/s^2 T^2
0.41667 s^2 = T^2
0.645497224 s = T
Now to get the velocity, multiply the time by the acceleration, giving
0.645497224 s * 12 m/s^2 = 7.745966692 m/s
After rounding to 2 significant figures, you get 7.7 m/s</span>
Answer:
619.8 N
Explanation:
The tension in the string provides the centripetal force that keeps the rock in circular motion, so we can write:

where
T is the tension
m is the mass of the rock
v is the speed
r is the radius of the circular path
At the beginning,
T = 50.4 N
v = 21.1 m/s
r = 2.51 m
So we can use the equation to find the mass of the rock:

Later, the radius of the string is decreased to
r' = 1.22 m
While the speed is increased to
v' = 51.6 m/s
Substituting these new data into the equation, we find the tension at which the string breaks:

Answer:
x = 0.0873 m
Explanation:
given,
length of clothesline = 10 m
the line sags to create an angle that is 1 degree below the horizontal on each end.
As mass is hang at the center the angle made let the deflection be 'x'
as the shirt is hang at the center distance will be equal to 5 m.
now




x = 0.0873 m
Hence, the cloth line will be x = 0.0873 m from the original length of the clothesline.