Identify the methods of increasing and decreasing friction and choose the correct option.
(i) The tyres of vehicles have treads.
(ii) Gymnasts often apply a coarse material on their hands.
(iii) Saliva in our mouth helps us to swallow food.
(iv) A surgeon powders his hand before pulling on his plastic gloves
| (i) | (ii) | (iii) | (iv) | |
| A | Increasing | Decreasing | Increasing | Decreasing |
| B | Decreasing | Increasing | Decreasing | Increasing |
| C | Increasing | Increasing | Decreasing | Decreasing |
| D | Decreasing | Decreasing | Increasing | Increasing |
Can anybody explain in option C. why would a gymnast apply powder to their hands to increase the friction?
Ans 2:
Class : Class 8
First of all, this question is also in the SOF book, secondly, whoever copied these questions really hates their job cuz in the solution they wrote a full stop
Ans 3:
Class : Class 8
Both statements are true. So, Option A is the correct answer. Kindly correct it, SOF.
Ans 4:
Class : Class 8
SOF, WHEN ARE YOU GOING TO LISTEN TO THE DEMANDS OF THE STUDENTS WHO ATTEMPT YOUR TEST PAPERS ON A REGULAR BASIS?! FRICTION ALWAYS ACTS OPPOSITE TO THE DIRECTION OF MOTION. MOREOVER, THE FIRST STATEMENT IS ALSO CORRECT, SINCE THE GROUND WILL EXERT FRICTION OPPOSITE TO THE DIRECTION OF MOTION OF THE PERSON. SINCE BOTH STATEMENTS ARE CORRECT AND THE SECOND STATEMENT IS THE CORRECT EXPLANATION OF THE FIRST ONE, OPTION A IS THE CORRECT ANSWER. It is a humble request to PLEASE rectify these incessant errors in test papers.
Ans 8:
Class : Class 8
kindly report if you think answer or solution given is wrong, otherwise SOF never reads the forum. Also the answer is rightly A