1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
allochka39001 [22]
3 years ago
8

A sanding disk with rotational inertia 1.2 10-3 kg·m2 is attached to an electric drill whose motor delivers a torque of 10 N·m a

bout the central axis of the disk. What are the following values about the central axis at the instant the torque has been applied for 70 ms?
Physics
1 answer:
tensa zangetsu [6.8K]3 years ago
4 0

Answer:

Angular momentum = 0.7 kg.m²/s

Angular velocity = 583.3 rad/s

Explanation:

1. The torque τ  is related to the angular momentum L by the relation

τ = ΔL/Δt

ΔL = τΔt

τ = 10 N. m

Δt = 70 ms = 70 × 10⁻³s

ΔL = (10 N. m) × (70 × 10⁻³s) = 700 × 10⁻³ kg.m²/s = 0.7 kg.m²/s

2. The rotational inertia I relates the angular momentum L to the angular velocity w

L = Iw

w = L/I

L =  0.7 kg.m²/s

I = 1.2 × 10⁻³ kg.m²

w = (0.7 kg.m²/s)/(1.2 × 10⁻³ kg.m²) = 583.3 rad/s

You might be interested in
A 100 kg roller coaster comes over the first hill at 2 m/sec (vo). The height of the first hill (h) is 20 meters. See roller dia
aleksandr82 [10.1K]

For the 100 kg roller coaster that comes over the first hill of height 20 meters at 2 m/s, we have:

1) The total energy for the roller coaster at the <u>initial point</u> is 19820 J

2) The potential energy at <u>point A</u> is 19620 J

3) The kinetic energy at <u>point B</u> is 10010 J

4) The potential energy at <u>point C</u> is zero

5) The kinetic energy at <u>point C</u> is 19820 J

6) The velocity of the roller coaster at <u>point C</u> is 19.91 m/s

1) The total energy for the roller coaster at the <u>initial point</u> can be found as follows:

E_{t} = KE_{i} + PE_{i}

Where:

KE: is the kinetic energy = (1/2)mv₀²

m: is the mass of the roller coaster = 100 kg

v₀: is the initial velocity = 2 m/s

PE: is the potential energy = mgh

g: is the acceleration due to gravity = 9.81 m/s²

h: is the height = 20 m

The<em> total energy</em> is:

E_{t} = KE_{i} + PE_{i} = \frac{1}{2}mv_{0}^{2} + mgh = \frac{1}{2}*100 kg*(2 m/s)^{2} + 100 kg*9.81 m/s^{2}*20 m = 19820 J

Hence, the total energy for the roller coaster at the <u>initial point</u> is 19820 J.

   

2) The <em>potential energy</em> at point A is:

PE_{A} = mgh_{A} = 100 kg*9.81 m/s^{2}*20 m = 19620 J

Then, the potential energy at <u>point A</u> is 19620 J.

3) The <em>kinetic energy</em> at point B is the following:

KE_{A} + PE_{A} = KE_{B} + PE_{B}

KE_{B} = KE_{A} + PE_{A} - PE_{B}

Since

KE_{A} + PE_{A} = KE_{i} + PE_{i}

we have:

KE_{B} = KE_{i} + PE_{i} - PE_{B} =  19820 J - mgh_{B} = 19820 J - 100kg*9.81m/s^{2}*10 m = 10010 J

Hence, the kinetic energy at <u>point B</u> is 10010 J.

4) The <em>potential energy</em> at <u>point C</u> is zero because h = 0 meters.

PE_{C} = mgh = 100 kg*9.81 m/s^{2}*0 m = 0 J

5) The <em>kinetic energy</em> of the roller coaster at point C is:

KE_{i} + PE_{i} = KE_{C} + PE_{C}            

KE_{C} = KE_{i} + PE_{i} = 19820 J      

Therefore, the kinetic energy at <u>point C</u> is 19820 J.

6) The <em>velocity</em> of the roller coaster at point C is given by:

KE_{C} = \frac{1}{2}mv_{C}^{2}

v_{C} = \sqrt{\frac{2KE_{C}}{m}} = \sqrt{\frac{2*19820 J}{100 kg}} = 19.91 m/s

Hence, the velocity of the roller coaster at <u>point C</u> is 19.91 m/s.

Read more here:

brainly.com/question/21288807?referrer=searchResults

I hope it helps you!

3 0
3 years ago
A forward horizontal force of 3 lb is used to pull a 60 lb sled at constant velocity on a frozen pond. the coefficent of (kineti
puteri [66]
It’s either 0.05 or 20. Assuming that the coefficient friction is a damping factor, I feel like 0.05 would be correct m
7 0
3 years ago
Which has the larger kinetic energy, a 10 g bullet fired at 400 m/s or a 80 kg bowling ball rolled at 6.5 m/s ?
mixer [17]
Formulae for Kinetic energy is:
Kinetic Energy= 1/2xmassx(velocity)^2

For comparison we need to have same units,thus we convert 10g into Kg.
10g/1000=0.01Kg

Input the value of bullet in the formulae;
Kinetic Energy= 1/2x0.01kgx(400)^2
K.E=800J

Input value of the ball:
Kinetic Energy=1/2x80kgx(6.5)^2
K.E=1690J

Which means that th Energy of the ball is more than the bullet.
7 0
3 years ago
A body of mass 2kg moves round a circle of radius 5m with a constant speed of 10m/s. Calculate the force toward the centre of th
antiseptic1488 [7]

Answer:

F = 5

Explanation:

F = m x v^2/r = 2 x 10^2/5 =200/5 = 40 (N)

5 0
2 years ago
An analogy makes a comparison between objects based on their similar qualities. Cassidy wanted to create an analogy for the moti
user100 [1]
The three phases of matter differ in properties just because of the proximity of their molecules. The solid phase is the most organized of all. Its atoms are compactly arranged together and has the strongest intermolecular forces to keep them together. This is why they have a definite shape and volume. The liquid phase have molecules that are far away from each other, but not as far as that of the gas phase. The liquid and gas phases can be lumped into one group called fluids because they have the same property - they take the shape and volume of their container.

To make an analogy, see the attached picture for your reference.

8 0
3 years ago
Read 2 more answers
Other questions:
  • Count Rumford concluded that heat energy is produced by
    11·1 answer
  • What is <img src="https://tex.z-dn.net/?f=sin%5E%7B-1%7D%280.61%29%3F" id="TexFormula1" title="sin^{-1}(0.61)?" alt="sin^{-1}(0.
    6·1 answer
  • Alex climbs to the top of a tall tree while his friend Gary waits on the ground below. Alex throws down a ball at 8 m/s from 50
    5·1 answer
  • A capacitor stores 7.6 × 10–11 C when the electric potential difference between the plates is 5.8 V. What is the electric potent
    8·1 answer
  • The symbol for speed is v and the symbol for time is t. If v = 13t + 11, then what is t?
    6·1 answer
  • Fuel cells have been developed that can generate a large amount of energy. For example, a hydrogen fuel cell works by combining
    15·1 answer
  • How high can a body vertically thrown with a speed of 40m/s raise after 3 sec (neglecting air
    8·1 answer
  • What kind of waves occur when the motion of the medium is parallel the the wave direction
    10·1 answer
  • An object on earth with a mass of 7.5 kg has a weight of
    10·1 answer
  • The brain is not a muscle, like the heart, that can be worked and built. Which BEST explains why a consistent exercise regime ha
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!