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
sammy [17]
3 years ago
13

A cooling fan is turned off when it is running at 900 rev/min. It turns 1700 revolutions before it comes to a stop.

Physics
1 answer:
Degger [83]3 years ago
6 0

Answer:

a)α = - 0.415 rad/s²

b)t=226.68 sec

Explanation:

Given

Initial angular speed

ωi= 900 rev/min

\omega_i=\dfrac{2\pi\times 900}{60}\ rad/s

ωi= 94.24

θ = 1700 rev

We know that

1 rev = 2π rad

θ = 3400π rad

Final angular speed ωf=0 rad/s

α=Angular acceleration

We know that

ωf² = ωi²+ 2 α θ

0² = 94.24²+ 2 x  3400π x α

α = - 0.415 rad/s²

Negative sign indicates that acceleration and speed is in opposite direction.

We also know that

ωf = ωi+  α t

0 = 94.24 - 0.415 x t

t=226.68 sec

a)α = - 0.415 rad/s²

b)t=226.68 sec

You might be interested in
A 0.111 kg hockey puck moving at 55 m/s is caught by a 80. kg goalie at rest. with what speed does the goalie slide on the frict
madreJ [45]

Answer:

0.076 m/s

Explanation:

Momentum is conserved:

m v = (m + M) V

(0.111 kg) (55 m/s) = (0.111 kg + 80. kg) V

V = 0.076 m/s

After catching the puck, the goalie slides at 0.076 m/s.

8 0
3 years ago
A box has a mass of 400 g. What minimum force is needed to lift it?
mart [117]

Answer: 3.92 N.

Explanation:

Your box weighs 400g, or 0.4kg. In order to lift it, you need to overcome the force of gravity. F = ma, and acceleration due to gravity is -9.8 m/s^2. So gravity acts on the box with a force of 0.4 kg * -9.8 m/s^2 = -3.92 N. A force of +3.92 N is required to overcome this.

5 0
3 years ago
How can a force change the motion of an object that is already moving?
lara [203]

Answer:They may cause motion to change

Explanation:They may cause motion; they may also slow, stop, or change the direction of motion of an object that is already moving. Since force cause changes in the speed or direction of an object, we can say that forces cause changes in velocity. Remember that acceleration is a change in velocity.

7 0
3 years ago
If a 2kg ball rolls down a ramp that is 15 meters long in 25 seconds, what is the
77julia77 [94]

Answer:

1.968504 ft/s

7 0
3 years ago
5. Which answer correctly summarizes the essential elements of a scientific theory?. A. descriptions of the natural world; based
Sedaia [141]
"Never become laws; based on strong scientific support; may change based on evidence" is the one answer among the following choices given in the question that correctly <span>summarizes the essential elements of a scientific theory. he correct option among all the options that are given in the question is the third option or option "C". </span>
3 0
3 years ago
Read 2 more answers
Other questions:
  • How much heat is released when 432 g of water cools down from 71'c to 18'c?
    13·1 answer
  • Matt forgot to put the fabric softener in the wash. As his socks tumbled in the dryer, they became charged. If a small piece of
    13·2 answers
  • A softball is thrown from the origin of an x-y coordinate system with an initial speed of 18 m/s at an angle of 35∘ above the ho
    12·1 answer
  • A wheel of mass M and radius R rolls on a level surface without slipping. If the angular velocity of the wheel about its center
    5·1 answer
  • Describe the behavior of magnets
    9·1 answer
  • Help? its due in like 12 minutes lolzz
    12·1 answer
  • A person on shore sees light
    9·1 answer
  • A father (75 kg) was standing watching TV, minding his own business when one of his kids (20 kg) approached him at 2m/s heading
    15·1 answer
  • Which statement is true about historical models of the solar system?
    8·1 answer
  • If Frequency F, velocity v, and density D are considered fundamental units, the dimensional formula for momentum will be :
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!