contestada

Suppose you start an antique car by exerting a force of 300 N on its crank for 0.250 s. What angular momentum (in kgm2s ) is given to the engine if the handle of the crank is 0.300 m from the pivot and the force is exerted to create maximum torque the entire time?

Respuesta :

Answer:

The angular momentum is 22.5 kgm²/s.

Explanation:

Given that,

Force = 300 N

Time = 0.250 s

Distance = 0.300 m

We need to calculate the torque

The torque is the product of the force and distance.

Using formula of torque

[tex]\vec{\tau}=\vec{F}\times \vec{r}[/tex]

Where, F = force

r = distance

Put the value into the formula

[tex]\vec{\tau}=300\times0.300[/tex]

[tex]\vec{\tau}=90\ N-m[/tex]

We need to calculate the angular momentum

The torque is equal to the rate of change of angular momentum of the particle.

[tex]\vec{\tau}=\dfrac{\Delta L}{\Delta t}[/tex]

[tex]\Delta L=\vec{\tau}\Delta t[/tex]

We know,

[tex]\Delta L=L_{f}-L_{i}[/tex]

Initial angular momentum is zero.

So, [tex]\Delta L=L_{f}-0[/tex]

Put the value into the formula

[tex]L_{f}=0.250\times90[/tex]

[tex]L_{f}=22.5\ Kgm^2/s[/tex]

Hence, The angular momentum is 22.5 kgm²/s.

The angular momentum given to the engine is; 22.5 kg.m/s²

What is the angular momentum?

We are given;

Force; F = 300 N

Time; t = 0.250 s

Distance; r = 0.300 m

Formula for torque is;

τ = F * r

τ = 300 * 0.3

τ = 90 N.m

Now, torque is equal to rate of change in angular momentum with time. Thus;

τ = (L_f - L_i)/Δt

90 = (L_f - 0)/0.25

L_f = 0.25 * 90

L_f = 22.5 kg.m/s²

Read more about angular momentum at; https://brainly.com/question/10124070