What is the greatest velocity which a falling object can achieve while falling through the air?

What is the magnitude of the gravitational force exerted by earth on a 9.0-kg brick when the brick is in free fall?

GarryVolchara [31]

The magnitude is 9.000kg

4 0

3 years ago

What's the closest to the thickness of a dime? A(millimeters)B(centimeters)C(decameters)D(meters)

djyliett [7]

B centimeters is the closest thickness to a dike because the dime's real thickness is 1.35

4 0

3 years ago

A 32.0 kg wheel, essentially a thin hoop with radius 1.20 m, is rotating at 280 rev/min. It must be brought to a stop in 15.0 s.

elena-14-01-66 [18.8K]

Answer:

A) Must be done 19806.62 joules of work.

B) The average power is 1320.44 Watts.

Explanation:

A) First, we're going to use the work-energy theorem that states total work ( $W$ ) done on an object is equal to the change in its kinetic energy ( $\Delta K$ ):

$W=\Delta K = K_{f}-K_{i}$ (1)

So, all we must do is to find the change on kinetic energy. Because we're working with rotational body, we should use the equation $K=\frac{I\omega^{2}}{2}$ for the kinetic energy so:

$\Delta K=\frac{I(\omega_{f})^{2}}{2}-\frac{I(\omega_{i})^{2}}{2}$ (2)

with $\omega_{i}$ the initial angular velocity, $\omega_{f}$ the final angular velocity (is zero because the wheel stops) and I the moment of inertia that for a thin hoop is $I=MR^{2}$ , using those on (2)