A force of 30 N is applied tangentially to the rim of a solid disk of radius 0.14 m. The disk rotates about an axis through its center and perpendicular to its face with a constant angular acceleration of 115 rad/s2. Determine the mass of the disk.

The mass of the disk is 3.73 kg

Explanation:

Given;

Applied force, F =  30 N

radius of solid disk, r = 0.14 m

angular acceleration of the disk, α = 115 rad/s²

Torque on the  rim of a solid disk is given as;

τ = F x r = I x α

where;

F is the applied force

r is the radius of the solid disk

I is moment of inertia

α is angular acceleration

Moment of inertia, I, of solid disk is given as;

I = ¹/₂mr²

m is the mass of the solid disk

Now, substitute this into the above equation;

F x r = I x α

F x r = ¹/₂mr² x α

F = ¹/₂mrα

m = 2F / rα

m = (2 x 30) / (0.14 x 115)

m = 3.73 kg

Thus, the mass of the disk is 3.73 kg

the rearrangement of particles in a physical change. hope this

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.