Which of the following are correct-A body of weight 1-N has potential energy of 1-J relative to the ground when it is at a height of 1-m-A 1-kg body has a kinetic energy of 1-J when its velocity is -2-ms-1-Instantaneous power due to force F is F -v-When a force retards the motion of a body- the work done is negative-

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Work Energy Theorem Application

Which of the ...

Question

Which of the following are correct?

A body of weight

1 N

has potential energy of

1 J

relative to the ground when it is at a height of

1 m

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

1 kg

body has a kinetic energy of

1 J

when its velocity is

\sqrt{2} {ms}^{- 1}

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Instantaneous power due to force

\to F

\to F . \to v

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

When a force retards the motion of a body, the work done is negative.

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct options are
A A body of weight $1 N$ has potential energy of $1 J$ relative to the ground when it is at a height of $1 m$ .
B A $1 kg$ body has a kinetic energy of $1 J$ when its velocity is $\sqrt{2} {ms}^{- 1}$ .
C Instantaneous power due to force $\to F$ is $\to F . \to v$ .
D When a force retards the motion of a body, the work done is negative.
a) Potential energy at height $h$ is $U = m g h = 1 \times 1 = 1 Joule$

b) $K . E . = \frac{1}{2} m v^{2} = \frac{1}{2} \times 1 \times (\sqrt{2})^{2} = 1 J$

c) Formula for instantaneous power is $P = \to F . \to v$

d) $W = F d cos (θ)$
When force retards angle between force and displacement is obtuse so $cos θ, W$ are negative.

Suggest Corrections

Similar questions

Q. A body of weight 1 newton has a potential energy of 1 joule relative to the ground when it is at a height of:

(a) Work is said to be done by a force only when _________

(b) Work done = Force $\times$ _________

(d) The S.I. unit of energy is ______

(e) The potential energy of a body is due to its ______ and kinetic energy of body is due to its ______

(f) Gravitational potential energy U = mass $\times$ force of gravity on unit mass $\times$ _________

(g) Kinetic energy = $\frac{1}{2} \times m a s s \times$ _________

(h) Power P = ______ / time taken.

(i) The S. I. unit of power is ______

(j) 1 H.P. = ______ W

Q. A body of mass 2 kg has a potential energy of 800 J when it is at a certain height. If it begins to fall, its velocity when its Kinetic energy and Potential energy are equal is

Q. A body of mass 1 kg has a kinetic energy of motion 8 J. Its linear momentum is equal to:

A body of mass 1 kg is taken from infinity to a point P. when the body reaches that point,it has a speed of 2m/s. the work done by conservative force is -5J. which of the following is true(assuming non-conservative and pseudo-forces to be absent).

a) work done by applied force is +7J.

b)the total energy possessed by the body at P is +7J

c)The potential energy possessed by the bodyat P is +5J

d) work done by all foeces together is equal to the change in KE.

Join BYJU'S Learning Program