363382
Assertion : A cyclist must adopt a zig-zag path while ascending a steep hill. Reason : The zig-zag path prevents the cyclist to slip down.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Cyclists choose a zig-zag path on a steep slope because it necessitates less force due to curvature of inclined path (spreading the effect of gravity.) (compared to moving in a straight line) \(\Rightarrow\) 'Zig-zag' is faster method. So correct option is (1)
PHXI05:LAWS OF MOTION
363383
If the co-efficient of static friction between the tyres and road is \(0.2,\) what is the shortest distance in which an automobile can be stopped when travelling at \(90\;km\;{h^{ - 1}}\)? (Take \(g = 10\;m{\rm{/}}{s^2}\) )
1 \(195.36\,m\)
2 \(156.25\,m\)
3 \(123.75\,m\)
4 \(173.15\,m\)
Explanation:
By Newton's third law, \(F = {f_s} = \mu R = \mu mg\) Also, \(F = ma\) \(\therefore \mu mg = ma\) \(\therefore \quad a = \mu g\) \(\therefore \quad a = 0.2\;g\) we have, \({v^2} = {u^2} - 2{\rm{as}}\) \(\therefore \quad {0^2} = {(25)^2} - 2 \times 0.2 \times 10 \times s\) \(\therefore \quad 0 = 625 - 4\;s\) \(\therefore 4\;s = 625\) \(\therefore s = 156.25\;m\)
PHXI05:LAWS OF MOTION
363384
Assertion : Use of ball bearing between two moving parts of a machine is a common practice Reason : Ball bearing reduces rolling friction and provides good stability.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
The use of ball bearings between two moving parts of a machine is indeed a common practice.The reason correctly explains that ball bearings reduce rolling friction and provide good stability, making them a preferred choice in many mechanical applications. So correct option is (1)
PHXI05:LAWS OF MOTION
363385
Assertion : Friction opposes relative motion and thereby dissipates energy in the form of heat. Reason : Friction is always an undesirable force.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Friction is often considered an undesirable force, but not always. In many situations, such as in machinery with multiple moving parts, friction can have negative consequences as it opposes relative motion and dissipates energy in the form of heat, among other effects. So correct option is (3).
363382
Assertion : A cyclist must adopt a zig-zag path while ascending a steep hill. Reason : The zig-zag path prevents the cyclist to slip down.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Cyclists choose a zig-zag path on a steep slope because it necessitates less force due to curvature of inclined path (spreading the effect of gravity.) (compared to moving in a straight line) \(\Rightarrow\) 'Zig-zag' is faster method. So correct option is (1)
PHXI05:LAWS OF MOTION
363383
If the co-efficient of static friction between the tyres and road is \(0.2,\) what is the shortest distance in which an automobile can be stopped when travelling at \(90\;km\;{h^{ - 1}}\)? (Take \(g = 10\;m{\rm{/}}{s^2}\) )
1 \(195.36\,m\)
2 \(156.25\,m\)
3 \(123.75\,m\)
4 \(173.15\,m\)
Explanation:
By Newton's third law, \(F = {f_s} = \mu R = \mu mg\) Also, \(F = ma\) \(\therefore \mu mg = ma\) \(\therefore \quad a = \mu g\) \(\therefore \quad a = 0.2\;g\) we have, \({v^2} = {u^2} - 2{\rm{as}}\) \(\therefore \quad {0^2} = {(25)^2} - 2 \times 0.2 \times 10 \times s\) \(\therefore \quad 0 = 625 - 4\;s\) \(\therefore 4\;s = 625\) \(\therefore s = 156.25\;m\)
PHXI05:LAWS OF MOTION
363384
Assertion : Use of ball bearing between two moving parts of a machine is a common practice Reason : Ball bearing reduces rolling friction and provides good stability.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
The use of ball bearings between two moving parts of a machine is indeed a common practice.The reason correctly explains that ball bearings reduce rolling friction and provide good stability, making them a preferred choice in many mechanical applications. So correct option is (1)
PHXI05:LAWS OF MOTION
363385
Assertion : Friction opposes relative motion and thereby dissipates energy in the form of heat. Reason : Friction is always an undesirable force.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Friction is often considered an undesirable force, but not always. In many situations, such as in machinery with multiple moving parts, friction can have negative consequences as it opposes relative motion and dissipates energy in the form of heat, among other effects. So correct option is (3).
363382
Assertion : A cyclist must adopt a zig-zag path while ascending a steep hill. Reason : The zig-zag path prevents the cyclist to slip down.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Cyclists choose a zig-zag path on a steep slope because it necessitates less force due to curvature of inclined path (spreading the effect of gravity.) (compared to moving in a straight line) \(\Rightarrow\) 'Zig-zag' is faster method. So correct option is (1)
PHXI05:LAWS OF MOTION
363383
If the co-efficient of static friction between the tyres and road is \(0.2,\) what is the shortest distance in which an automobile can be stopped when travelling at \(90\;km\;{h^{ - 1}}\)? (Take \(g = 10\;m{\rm{/}}{s^2}\) )
1 \(195.36\,m\)
2 \(156.25\,m\)
3 \(123.75\,m\)
4 \(173.15\,m\)
Explanation:
By Newton's third law, \(F = {f_s} = \mu R = \mu mg\) Also, \(F = ma\) \(\therefore \mu mg = ma\) \(\therefore \quad a = \mu g\) \(\therefore \quad a = 0.2\;g\) we have, \({v^2} = {u^2} - 2{\rm{as}}\) \(\therefore \quad {0^2} = {(25)^2} - 2 \times 0.2 \times 10 \times s\) \(\therefore \quad 0 = 625 - 4\;s\) \(\therefore 4\;s = 625\) \(\therefore s = 156.25\;m\)
PHXI05:LAWS OF MOTION
363384
Assertion : Use of ball bearing between two moving parts of a machine is a common practice Reason : Ball bearing reduces rolling friction and provides good stability.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
The use of ball bearings between two moving parts of a machine is indeed a common practice.The reason correctly explains that ball bearings reduce rolling friction and provide good stability, making them a preferred choice in many mechanical applications. So correct option is (1)
PHXI05:LAWS OF MOTION
363385
Assertion : Friction opposes relative motion and thereby dissipates energy in the form of heat. Reason : Friction is always an undesirable force.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Friction is often considered an undesirable force, but not always. In many situations, such as in machinery with multiple moving parts, friction can have negative consequences as it opposes relative motion and dissipates energy in the form of heat, among other effects. So correct option is (3).
363382
Assertion : A cyclist must adopt a zig-zag path while ascending a steep hill. Reason : The zig-zag path prevents the cyclist to slip down.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Cyclists choose a zig-zag path on a steep slope because it necessitates less force due to curvature of inclined path (spreading the effect of gravity.) (compared to moving in a straight line) \(\Rightarrow\) 'Zig-zag' is faster method. So correct option is (1)
PHXI05:LAWS OF MOTION
363383
If the co-efficient of static friction between the tyres and road is \(0.2,\) what is the shortest distance in which an automobile can be stopped when travelling at \(90\;km\;{h^{ - 1}}\)? (Take \(g = 10\;m{\rm{/}}{s^2}\) )
1 \(195.36\,m\)
2 \(156.25\,m\)
3 \(123.75\,m\)
4 \(173.15\,m\)
Explanation:
By Newton's third law, \(F = {f_s} = \mu R = \mu mg\) Also, \(F = ma\) \(\therefore \mu mg = ma\) \(\therefore \quad a = \mu g\) \(\therefore \quad a = 0.2\;g\) we have, \({v^2} = {u^2} - 2{\rm{as}}\) \(\therefore \quad {0^2} = {(25)^2} - 2 \times 0.2 \times 10 \times s\) \(\therefore \quad 0 = 625 - 4\;s\) \(\therefore 4\;s = 625\) \(\therefore s = 156.25\;m\)
PHXI05:LAWS OF MOTION
363384
Assertion : Use of ball bearing between two moving parts of a machine is a common practice Reason : Ball bearing reduces rolling friction and provides good stability.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
The use of ball bearings between two moving parts of a machine is indeed a common practice.The reason correctly explains that ball bearings reduce rolling friction and provide good stability, making them a preferred choice in many mechanical applications. So correct option is (1)
PHXI05:LAWS OF MOTION
363385
Assertion : Friction opposes relative motion and thereby dissipates energy in the form of heat. Reason : Friction is always an undesirable force.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Friction is often considered an undesirable force, but not always. In many situations, such as in machinery with multiple moving parts, friction can have negative consequences as it opposes relative motion and dissipates energy in the form of heat, among other effects. So correct option is (3).
