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Syeda answered 1 year(s) , 8 month(s) ago

Derive the expression kinetic energy, potential energy

Derivation for the equation of Potenstial Energy:
Let the work done on the object against gravity = W
                 Work done, W = force × displacement...

Asked by Pranesh

Dec 24

  • 3 Answers
  • 6 Likes
  • 59030 Views
Fibin answered 3 year(s) , 10 month(s) ago

Calculate the work required to be done to stop a car of 1500 kg moving at a velocity of 60 km/h?

m=1500kg

u= 60km/h =60* 5/18 = 50/3m/s

v =0m/s

w = change in its KE.

initial KE =1/2 mu 2

final KE=1/2mv²
...

Asked by Milan

Feb 6

  • 7 Answers
  • 2 Likes
  • 34167 Views
Ravinder answered 4 year(s) , 11 month(s) ago

Derivation of the equation for kinetic energy (K.E = ½ m v 2)

Expression for  Kinetic energy(E k )-
Consider an object with mass m, moving with initial velocity u. Let a force F, act on it causing a displacement s, along the direction of force and acce...

Asked by Madhusudhan

Mar 12

  • 3 Answers
  • 4 Likes
  • 18089 Views
Janhavi answered 3 year(s) , 11 month(s) ago

1. What is work done by a coolie walking on level road with load on his head? 2. Why is work done zero when, the direction of displacement and the direction of force on a body are perpendicular to each other?

1. Work done by a coolie, walking  on level road with load on his head,  on the load is zero.
2. Work done = Force x displacement

W = F.s = Fs cos θ

where  θ is the angle be...

Asked by Rushin

Feb 17

  • 2 Answers
  • 2 Likes
  • 16844 Views
Janhavi answered 3 year(s) , 11 month(s) ago

An electric bulb of 60W is used for 6 hours per day calculate the units of energy consumed in one day by the bulb.

Electrical energy consumed by the bulb per day = P x t = 60 W x 6h = 360 Wh

1 unit = 1 kW h = 1000 W h
1 W h = (1/1000) unit
360 W h = 0.360 unit
Electrical energy consum...

Asked by Ritik

Mar 4

  • 1 Answer
  • 3 Likes
  • 16219 Views
Syeda answered 1 year(s) , 8 month(s) ago

what are three characteristics of sound waves ? On what factors do they depend .

Answer.

i) Pitch depends on the frequency of the sound waves produced by the source.
 
(ii) Quality (or Timbre) of the sound depends on wave form....

Asked by Varunkumar

Jan 2

  • 2 Answers
  • 2 Likes
  • 14859 Views
Rahul answered 2 year(s) , 11 month(s) ago

Is Potential energy a vector quantity or scalar?

Its a scalar quantity

Asked by Nipunn

Oct 14

  • 8 Answers
  • 3 Likes
  • 13344 Views
Syeda answered 1 year(s) , 8 month(s) ago

State the factors on which work done depends?

Answer.

1) a force is applied on the object

2)there is a displacement in the direction of the force of the object

Asked by Ayushi

Mar 15

  • 4 Answers
  • 1 Like
  • 13196 Views
Garvita commented 4 year(s) ago

A body of mass 2 kg falls from rest. What will be its kinetic energy during the fall at the end of 2 s?(assume g=10.)

Mass of the body m = 2 kg
Initial speed u = 0
t = 2 s
g = 10 m/s 2.
For a freely falling body the final velocity at the end of t s is given by
v = u + gt = 0...

Asked by Garvita

Jan 5

  • 1 Answer
  • 0 Like
  • 12131 Views
Syeda answered 1 year(s) , 11 month(s) ago

commercial unit of energy

Answer.

Commercial Unit of Energy. The SI unit joule is too small to express very large quantities of energy. Hence we use a bigger unit called kilowatt hour (kWh) to express energy. 1 kWh is th...

Asked by Trisha

Feb 18

  • 3 Answers
  • 2 Likes
  • 11866 Views
Janhavi answered 3 year(s) , 10 month(s) ago

A force is applied on a car of mass 1500 kg, so that its speed increases from 54 km/h to 72 km/h. Find the work done by the force on the car.

Mass of car m = 1500 kg
Initial velocity = 54 km/h = 54 x 5/18 = 15 m/s
Final velocity = 72 km/h = 72 x 5/18 = 20 m/s 
( 1 km/h = 1000 m/ (3600 s) = 5/18 m/s
Initial kinetic ener...

Asked by Fibin

Mar 16

  • 2 Answers
  • 2 Likes
  • 11599 Views
Amarnathreddy answered 4 year(s) ago

Derive the formula for work done by a constant force.


Let the initial velocity = u, 
Final velocity = v,
Uniform acceleration = a, and
Displacement = S, then

v 2 - u 2 = 2aS This gives  ...

Asked by Rommel

Jan 11

  • 1 Answer
  • 1 Like
  • 8172 Views
Janhavi answered 3 year(s) ago

A porter lifts a luggage of 15 kg from the ground and put it on his head 1.5 m above the ground . Calculate the work done by him on the luggage.

Work done by the porter on the luggage = Force x displacement
                                                                     = mgh
                                                         ...

Asked by Amir

Jan 14

  • 2 Answers
  • 2 Likes
  • 7830 Views
Amarnathreddy answered 5 year(s) ago

can any object have Mechanical energy if its momentum is 0? explain.

Can any object have Mechanical energy if its momentum is 0? Explain.
Answer:  Momentum is the product of mass and velocity of a body, for a body mass never be zero but...

Asked by Merlin

Jan 14

  • 1 Answer
  • 0 Like
  • 7247 Views
Janhavi answered 3 year(s) , 10 month(s) ago

Water is falling on the blades of a turbine at the rate of 8 x 102 kg per minute, height of fall is 50 m, calculate the power given to turbine. (g=10 m/s2)

Power = Work done/time
           = mgh/t
           = (8 x 10 2/60)(kg/s) x (10 m/s 2) x 50 m
           = 6666.6 W   
           = 6.6666 kW

Asked by Pralav

Mar 8

  • 1 Answer
  • 2 Likes
  • 6854 Views
Agam answered 9 month(s) , 22 day(s) ago

A truck of mass 1800 kg is moving witha speed 54 km/h when brakes are appiled it stops with uniform retardation at a distance of 200 m.Calculate the force appiled by the brakes of the truck and the work done before stopping.

Mass of the truck m = 1800 kg
Initial speed u = 54 km/h = 15 m/s
Final speed v = 0
s = 200 m
We have v 2 - u 2 = 2as
a = (v 2 - u 2 )/(2s)
= (0 - 15 2 )/400 =...

Asked by Nufaiz

Mar 1

  • 2 Answers
  • 1 Like
  • 6208 Views
Janhavi answered 4 year(s) , 3 month(s) ago

Are various energy forms interconvertible?

Yes, various forms of energy are interconvertible. Look at the following examples.

  • Sound energy is converted into electrical energy in a microphone.
  • Electrical energy is converted into so
...

Asked by Anjum

Oct 11

  • 1 Answer
  • 0 Like
  • 5806 Views
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