English

In Which of the Following Case the Work Done by a Force Will Be Maximum : When the Angle Between the Direction of Force and Direction of Motion is 0° Or 90°? - Science

Advertisements
Advertisements

Question

In which of the following case the work done by a force will be maximum : when the angle between the direction of force and direction of motion is 0° or 90°?

Answer in Brief

Solution

The relation between work, force, distance and angle between the two is:
W = (F) (S) cos θ
Where,
(W) - Work done
(F) - Force
(S)- Displacement
(θ)- Angle between force and displacement
When the force is perpendicular to the direction of motion, and hence, the work done is also zero.
When the direction of force is similar the direction of motion, and hence, the work done is maximum.

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Work and energy - Very Short Answers 1 [Page 149]

APPEARS IN

Lakhmir Singh Physics (Science) [English] Class 9 ICSE
Chapter 4 Work and energy
Very Short Answers 1 | Q 74 | Page 149

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

An object thrown at a certain angle to the ground moves in a curved path and falls back to the ground. The initial and the final points of the path of the object lie on the same horizontal line. What is the work done by the force of gravity on the object?


The S.I. unit of work is


No work is done by a force if the body


A force of 30 N acts on a body and moves it through a distance of 5 m in the direction of force. Calculate the work done by the force.


A body of mass 5 kg falls from a height of 10 m to 4 m. Calculate:

The loss in potential energy of the body, 


Find the kinetic energy of a body of mass 1 kg moving with a uniform velocity of 10 m s-1.


A boy throws a rubber ball vertically upwards. What type of work, positive or negative, is done : by the force applied by the boy?
(a) by the force applied by the boy?
(b) by the gravitational force of earth?


Ravi applied a force of  10 N and moved a book 30 cm in the direction of the force. How much was the work done by Ravi?


A uniform circular motion is an accelerated motion. Justify it.


Write an expression for the work done against gravity.


What is meant by equilibrium?

How fast should a boy weighting 30 kg run so that his kinetic energy is 375 joule?


List any six forms of energy and write a short note on each of them.


A bullet is of mass 'm' g and is moving with a velocity 'v' m/s. Find the kinetic energy of the bullet when
(a) The mass is doubled,
(b) The velocity is tripled.


An electric motor of power 100 W is used to drive the stirrer in a water bath. If 50% of the energy supplied to the motor is spent in stirring the water. Calculate the work done on the water in one minute.


What is work?


Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.

A wind-mill is lifting water from a well.


Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.

An engine is pulling a train.


A force of F = (5y + 20) `hat"j"` N acts on a particle. The work done by this force when the particle is moved from y = 0 m to y = 10 m is ______ J.


A uniform chain of length 2 m is kept on a table such that a length of 60 cm hangs freely from the edge of the table. The total mass of the chain is 4 kg. What is the work done in pulling the entire chain on the table?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×