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
klio [65]
3 years ago
12

A ball attached to a string is whirled around in a horizontal circle having a radius r. If the radius of the circle is changed t

o 4r and the same centripetal force is applied by the string, the new speed of the ball is which of the following?a. One-quarter the original speed
b. Twice the original speed
c. One-half the original speed
d. Four times the original speed
Physics
1 answer:
LenKa [72]3 years ago
5 0

Answer:

Option D: Four times the original speed.

Explanation:

A centripetal force accelerates a body by changing the direction of the body's  velocity without changing the body's speed.

The speed(v) is therefore constant, thereby making the magnitudes of the of the acceleration and the force constant.

The formula used to calculate the Centripetal force is given below:

F = \frac{mv^2}{r}

where F represents the Centripetal force, m represents the mass of the moving body, v represents the speed or velocity at which the body is moving and r represents the radius.

Making the speed the subject of the formula: v^{2} = \frac{rF}{m} \\

Therefore, when the radius (r) is changed to 4r, i.e r = 4r

speed(v) becomes v^2 = \frac{4rF}{m}

After comparing, the difference between the speeds is Four times the original speed.

You might be interested in
HURRY PLZ
Natali [406]

The answer correct is C:The cell is most likely prokaryotic ,but it could be eukaryotic since some unicellular are eukaryotic.


5 0
3 years ago
To understand how to find the velocities of objects after a collision.
trasher [3.6K]

There are some information missing on Part D: Let the mass of object 1 be m and the mass of object 2 be 3m. If the collision is perfectly inelastic, what are the velocities of the two objects after the collision? Give the velocity v_1 of object one, followed by object v_2 of object two, separated by a comma. Express each velocity in terms of v.

Answer: Part A: v_1 = 0; v_2 = v

Part B: v_1 = v_2 = \frac{v}{2}

Part C: v_1 = \frac{v}{3}; v_2 = \frac{4v}{3}

Part D: v_1 = v_2 = \frac{v}{4}

Explanation: In elastic collisions, there no loss of kinetic energy and momentum is conserved. Momentum is determined as p = m.v and kinetic energy as K = \frac{1}{2}m.v^{2}

Conserved means that the amount of initial momentum is equal to the amount of final momentum:

m_{1}.v_{1i} + m_{2}.v_{2i} = m_{1}.v_{1f} + m_{2}.v_{2f}

No loss of energy means that initial kinietc energy is the same as the final kinetic energy:

\frac{1}{2}(m_{1}.v_{1i} + m_{2}.v_{2i}) = \frac{1}{2} (m_{1}.v_{1f} + m_{2}.v_{2f}  )

To determine the final velocities of each object, there are 2 variables and two equations, so working those equations, the result is:

v_{2f} = \frac{2.m_{1} } {m_{1} + m_{2} }.v_{1i}  + \frac{(m_{2} - m_{1})}{m_{1} + m_{2} } . v_{2i}

v_{1f} = \frac{m_{2} - m_{1} }{m_{1} + m_{2} } . v_{1i} + \frac{2.m_{2} }{m_{1} + m_{2} } .v_{2i}

For all the collisions, object 2 is static, i.e. v_{2i} = 0

<u>Part A</u>: Both objects have the same mass (m), v_{1i} = v and collision is elastic:

v_1 = \frac{m_{2} - m_{1}}{m_{1} + m_{2} } . v_{1i}

v_1 = 0

v_2 = \frac{2.m_{1} }{m_{1} + m_{2}}.v_{1i}

v_2 = \frac{2.m}{m+m}.v

v_2 = v

When the masses are the same and there is an object at rest, the object in movement stops and the object at rest has the same same velocity as the object who hit it.

<u>Part B</u>: Same mass but collision is inelastic: An inelastic collision means that after it happens, the two objects has the same final velocity, then:

m_{1}.v_{1i} + m_{2}.v_{2i} = m_{1}.v_{1f} + m_{2}.v_{2f}

m_{1}.v_{1i} = (m_{1}+m_{2}).v_{f}

v_{f} =  \frac{m_{1}.v_{1i}}{m_{1} + m_{2} }

v_1 = v_2 = \frac{m.v}{m+m}

v_1 = v_2 = \frac{v}{2}

<u>Part C:</u> Object 1 is 2m, object 2 is m and elastic collision:

v_1 = \frac{m_{2} - m_{1}}{m_{1} + m_{2} } . v_{1i}

v_1 = \frac{2m - m}{2m + m } . v

v_1 = \frac{v}{3}

v_2 = \frac{2.m_{1} }{m_{1} + m_{2}}.v_{1i}

v_2 = \frac{2.2m}{2m+m}.v

v_2 = \frac{4v}{3}

<u>Part D</u>: Object 1 is m, object is 3m and collision is inelastic:

v_1 = v_2 = v_{f} =  \frac{m_{1}.v_{1i}}{m_{1} + m_{2} }

v_1 = v_2 = \frac{m}{m+3m}.v

v_1 = v_2 = \frac{v}{4}

5 0
3 years ago
a 64 l gas tank is filled completely is 15 degree celsius how much gasoline overflows into can get up to 35 degree celsius while
o-na [289]

Answer:

Volume of gasoline overflow(v)= 40/9 L (I.e. 4.44 L)

Explanation:

Use <u>v1</u><u>/</u><u>T1</u><u>=</u><u>v2</u><u>/</u><u>T2</u>

.....overflow(V)=v2-v1

<u>Note</u><u>;</u> <em>Take</em><em> </em><em>temperature</em><em> </em><em>in</em><em> </em><em>absolute</em><em> </em><em>scale</em><em> </em><em>or</em><em> </em><em>kelvin</em><em> </em><em>scale</em><em> </em>

3 0
3 years ago
!! 50 points spent, easy points for you. 8th-grade science/physics !!
luda_lava [24]

Answer:

1.mirage

2.lens

3.concave lens

4.convex lens

5.index of refraction

Explanation:

IQ=999999

7 0
3 years ago
A top fuel dragster with a mass of 500.0 kg starts from rest and completes a quarter mile (402 m) race in a time of 5.0 s. The d
blsea [12.9K]

The average power needed to produce this final speed is 1069.1 hp.

Mass of the dragster,  m = 500.0 kg,

Displacement travelled by the dragster,  s = 402 m,

Time taken in this travel,  t = 5.0 s,

Final velocity of the dragster,  v = 130 m/s.

Let the initial velocity of the dragster be u and acceleration be a.

Using kinematical equation,  s = ut + (1/2)at^2.

402  =  u*5  + (1/2)*a*5^2

10*u + 25*a  = 804.      ...........(1)

Using kinematical equation, v = u +at.

130 = u + 5*a

5*u + 25*a = 650.       .............(2)

Solving (1)and (2), we get,

u =  30.8 m/s.

According to work-energy theorem,

Work done = change in kinetic energy

W  = (1/2)*m*(v^2 - u^2)

W = (1/2)*500*(130^2 - 30.8^2)

W  =  3987840. J

Therefore power rating of the dragster is given by,

P  ⇒  W/t. =  3987840/5 = 797568 watt.

P  ⇒ 797568/746 =  1069.1 hp.

Learn more about Power rating here brainly.com/question/20137708

#SPJ4

5 0
2 years ago
Read 2 more answers
Other questions:
  • When the height of the cylinder increased by a factor of 5from 100 m to 500 m, what happened to the cylinder's
    14·1 answer
  • PLEASE HELPPPPP!!Calculate the net force acting on obiect A. In your answer, be sure to include the number, unit, and
    8·1 answer
  • If the length of one side of a square is 12.0 m, what is the perimeter of the square?
    13·1 answer
  • A 26-cm-long wire with a linear density of 20 g/m passes across the open end of an 86-cm-long open-closed tube of air. If the wi
    9·1 answer
  • Sound travels fastest through
    9·1 answer
  • Which floor type had the least amount of friction?
    6·2 answers
  • When two ocean plates move away from each other that is called?
    11·1 answer
  • What is your zodiac sign?
    7·1 answer
  • Answer? physics Q for 3rd secondry
    8·1 answer
  • Ysical Science A
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!