Page 1 - Home Assignment
P. 1
SAI INTERNATIONAL SCHOOL
Class8
Home Assignment
Subject-Physics
CH-Friction
Subtopic-Methods to increase and decrease friction
INSTRUCTIONS:
.
For Assertion& Reason question follow the following directions.
DIRECTION: Each of these questions contains an Assertion followed by Reason. Read them
carefully and answer the question on the basis of following options. You have to select the one
that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of
Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If Assertion is incorrect but Reason is correct.
(e) If Assertion & Reason both are incorrect.
1. Assertion: Machine parts needs to be oiled regularly. 1
Reason: Lubricants decrease friction.
2. Assertion: Heavy Suitcase are fit with rollers. 1
Reason: It gives a nice look.
Fill in the blanks
3. Friction causes __________ and ______________ 1
4. Sprinkling of powder on the carom board _____________ friction. 1
True/ False
5. Lubricants reduces friction. 1
6. Friction can be reduced by pressing the surface hard against each other. 1
Subjective Question
7. Explain why sportsmen use shoes with spikes. 1