English

A Moving Object of Mass 30 Kg Has 60 J of Kinetic Energy. What is Its Speed? - Physics

Advertisements
Advertisements

Question

A moving object of mass 30 kg has 60 J of kinetic energy. What is its speed?
Numerical

Solution

K.E = `1/2` mv²

60 = `1/2` (30) (v)²

or v² = 4 m/s

or v= 2 m/s

shaalaa.com
  Is there an error in this question or solution?
Chapter 1: Force, Work, Energy and Power - Exercise 1.5 i [Page 53]

APPEARS IN

Frank Physics - Part 2 [English] Class 10 ICSE
Chapter 1 Force, Work, Energy and Power
Exercise 1.5 i | Q 12 | Page 53

RELATED QUESTIONS

When do we say that work is done?


MULTIPLE CHOICE TYPE

In an electric cell which in use, the change in energy is from:


When do we say that work is done? Write the formula for the work done by a body in moving up against gravity. Give the meaning of each symbol which occurs in it.


A max X goes to the top of a building by a vertical spiral staircase. Another man Y of the same mass goes to the top of the same building by a slanting ladder. Which of the two does more work against gravity and why?


In case of negative work, the angle between the force and displacement is :


A man lifts a mass of 10 kg from the floor to a shelf 4 meter high. If g = 10 ms-2, what is the work done?


What do you mean by the term 'work'?

What should be the angle between the directions of the displacement and the applied force so that the work done is zero?

Give two examples of P.E.

Define the unit 'watt'. How is it related to horse power?

A body does 20 J of work in 10 s. What is its power?


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


Give an example 
Chemical energy changes to heat energy.


Give an example

Light energy changes to electrical energy.


Find the kinetic energy of a car of mass 1000 kg traveling at 72 km/h.

A canon ball of mass 500g is fired with a speed of 15m/s-1. Find: its momentum.


How much energy is gained by a box of mass 20 kg when a man, runs carrying the box with a speed of 3 m/s-1 to catch the bus?


In what way does an ‘Ideal machine’ differ from a ‘Practical machine’?


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

A green plant is carrying out photosynthesis.


A man squatting on the ground gets straight up and stand. The force of reaction of ground on the man during the process is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×