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Syeda
answered
1 year(s)
, 10 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...

- 3 Answers
- 7 Likes
- 67769 Views

Fibin
answered
4 year(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

...

- 7 Answers
- 2 Likes
- 40774 Views

Ravinder
answered
5 year(s)
, 1 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
- 25136 Views

Amarnathreddy
answered
5 year(s)
, 1 month(s) ago

A bullet fired into a fixed target loses half of its velocity after penetrating 3cm. How much futher it will penetrating before coming to rest assuming that it faces constant resistance to motion.

- 1 Answer
- 2 Likes
- 23523 Views

Janhavi
answered
4 year(s)
, 1 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...

- 1 Answer
- 4 Likes
- 20049 Views

Janhavi
answered
4 year(s)
, 1 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...

- 2 Answers
- 2 Likes
- 18585 Views

Syeda
answered
1 year(s)
, 10 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
- 17036 Views

Syeda
answered
2 year(s)
, 2 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...

- 3 Answers
- 3 Likes
- 15309 Views

Rahul
answered
3 year(s)
, 1 month(s) ago

Is Potential energy a vector quantity or scalar?

Its a scalar quantity

- 8 Answers
- 3 Likes
- 14086 Views

Syeda
answered
1 year(s)
, 10 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

- 4 Answers
- 1 Like
- 13771 Views

Garvita
commented
4 year(s)
, 3 month(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...

- 1 Answer
- 0 Like
- 13448 Views

Janhavi
answered
4 year(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...

- 2 Answers
- 2 Likes
- 12675 Views

Amarnathreddy
answered
5 year(s)
, 2 month(s) ago

Deriva a relation between momentum and kinetic energy

- 1 Answer
- 1 Like
- 11356 Views

Amarnathreddy
answered
4 year(s)
, 3 month(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 ...

- 1 Answer
- 1 Like
- 9308 Views

Janhavi
answered
4 year(s)
, 2 month(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

...

- 2 Answers
- 2 Likes
- 8758 Views

Amarnathreddy
answered
5 year(s)
, 3 month(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...

- 1 Answer
- 0 Like
- 8301 Views

Janhavi
answered
4 year(s)
, 1 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

- 1 Answer
- 2 Likes
- 7394 Views

Agam
answered
11 month(s)
, 27 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 =...

- 2 Answers
- 1 Like
- 6857 Views

Janhavi
answered
4 year(s)
, 6 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

- 1 Answer
- 0 Like
- 6165 Views

Amarnathreddy
answered
4 year(s)
, 1 month(s) ago

What is meant by average power?

Average power the ratio of the total work done by the body and the total time taken.

Power = Energy consumed/ Time taken = work done / Time

- 2 Answers
- 3 Likes
- 6137 Views

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