In a laundromat, during the spin-dry cycle of a washer, the rotating tub goes from rest to its maximum angular speed of 4.7 rev/s in 8.3 s. You lift the lid of the washer and notice that the tub decelerates and comes to a stop in 17.5 s. Assuming that the tub rotates with constant angular acceleration while it is starting and stopping, determine the total number of revolutions undergone by the tub during this entire time interval.

Number of revolutions = Δθ = 60.63 revs

Explanation:

The angular acceleration of the washer is given by

α = (ωf - ωi)/Δt

Where ωf is the initial angular speed, ωi is the final angular speed and Δt is the interval of time during this acceleration.

α = (4.7 - 0)/8.3

α = 0.56 rev/s²

As we know from the equation of kinematics,

2αΔθ = ωf² - ωi²

Where Δθ is the change in angular displacement of the washer.

Δθ = (ωf² - ωi²)/2α

Δθ = (4.7² - 0²)/2*0.56

Δθ = 19.72 revs

Now the tub decelerates and comes to a stop in 17.5 s

α = (ωf - ωi)/Δt

α = (-4.7 - 0)/17.5

α = -0.27 rev/s²

the corresponding change in angular displacement of the washer is

Δθ = (ωf² - ωi²)/2α

Δθ = (0² - 4.7²)/2*-0.27

Δθ = 40.91 revs

Therefore, the total number of revolutions undergone by the tub during this entire time interval is

Δθ = 19.72 + 40.91

Δθ = 60.63 revs

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.

truck y has a greater velocity than truck x.