# data[].attributes.body
NSS TRAINING COLLEGE OTTAPALAM- ICT WORKSHOP
DIGITAL TEXT

Name of the teacher :PRAVEENA K   Date  :  20/5/22
Department : Physical Science          Class       : 9th
Subject    : Physics                            Duration  : 40 minutes
Unit         : Work, Energy and Power
Topic      : Kinetic Energy

Objectives:
The study of kinetic energy helps

1. To understand the energy possessed by objects due to its motion and define it.

2. To give examples of objects having kinetic energy.

3. To analyze situations and distinguish if objects possess kinetic energy or not.

4. To understand the two factors affecting kinetic energy.

5. To give the equation of kinetic energy for solving numerical problems.

# data[].attributes.body
Energy is defined as the capacity to do work.

Work is done to displace the box from position1 to position2 shown in the figure.
Work,   W= Force * Displacement
If F is the force and d is the displacement, W=F*d
Unit of work is Joule or Newton second.

# data[].attributes.body
There are different forms of energy that we see around us in daily life. The given image illustrates some of them.

Among the different forms of energy mechanical energy is one of the important.
Mechanical energy otherwise known as moving energy consist of two types
1. Kinetic energy                                  2. Potential energy

# data[].attributes.body
Consider the situation of a toy car hitting a plastic ball kept at rest as shown in the figure.
What happens to the ball when the car hits?
Is there any force applied on the ball?
Is there any work done on the ball?
How did the car get the energy to hit the ball?
ANSWERS
The ball got displaced when the car hits
Force was applied on the ball by the car
Yes, work was done on the ball by the car
Work done= Force * Displacement
W=F*d
The car gets energy to hit the ball by its motion.

Kinetic Energy Definition
The energy possessed by a body by virtue of its motion is the kinetic energy.
Examples: - Car moving on a road, ball rolling down a hill.

# data[].attributes.body
Analyze the situations shown and make a table of objects having kinetic energy and objects which do not have kinetic energy.

OBJECTS HAVING KINETIC ENERGY

Flying aircraft

Bullet fired from gun

Running animal

OBJECTS NOT HAVING KINETIC ENERGY

Dog sleeping

Vehicles parked

Boy standing

# data[].attributes.body
Factors affecting kinetic energy
Experiment 1 : When ball rolling down from slopes of different heights hit a car at rest on the bottom of slope, the velocity of motion changes in different cases and motion of car will be more when velocity is high.

Experiment 2: When paper cups are strike with balls of different mass, the cups have more displacement when mass of ball is high.

Thus the two factors affecting kinetic energy are
1. Velocity of the moving body
2. Mass of the moving body

# data[].attributes.body
m is the mass and v is the velocity

# data[].attributes.body
https://youtu.be/dcTUujDtCLI

# data[].attributes.attachment_link.readable_text
Kinetic Energy

0:00

8:50

Back

# data[].attributes.attachment_link.readable_text
0:00 / 4:24•Watch full video

# data[].attributes.attachment_link.readable_text
9th Std EM Physics Vol-2.pdf

9th Std EM Physics Vol-2.pdf

# data[].attributes.attachment_caption
Work , Energy and Power - Let us assess & Answers | Class 9 English Medium

# data[].attributes.attachment_link.readable_text
Answer)
a) Potential energy
b) Potential energy
c) Potential energy lesser. Kinetic energy

Download App and View Complete Answer for FREE

Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 9 English Medium Tuition

Answer)
u = 3m/s        v = 0
a = g = -10m/s² (Velocity of a body moving upwards is decreasing so acceleration is negative)Download App and View Complete Answer for FREE

Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 9 English Medium Tuition

Answer)
Yes, possible. A coconut on a coconut tree has potential energy, but it has no

Download App and View Complete Answer for FREE

Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 9 English Medium Tuition

Answer)

1. Positive work

2. Negative work

3. Negative work

4. Positive
Download App and View Complete Answer for FREE

Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 9 English Medium Tuition

Answer)
m = 1000 kg
v = 72 km/hr = 20 m/s
Work = difference of kinetic energy
= (Download App and View Complete Answer for FREE

Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 9 English Medium Tuition

# data[].attributes.attachment_link.title
Work , Energy and Power - Let us assess & Answers | Class 9 English Medium

# data[].attributes.attachment_link.description
Work , Energy and Power - Let us assess Class 9 English Medium

# data[].attributes.attachment_caption
Forms of Energy : Kinetic Energy | Part 1/1 | English | Class 9

# data[].attributes.attachment_link.readable_text
Forms of Energy : Kinetic Energy | Part 1/1 | English | Class 9

# data[].attributes.attachment_link.title
Forms of Energy : Kinetic Energy | Part 1/1 | English | Class 9

# data[].attributes.attachment_link.readable_text
Click to view in fullscreen