MCQs
Read every question, see the correct answer, and understand the explanation at your own pace. Study mode has no timer and no negative marking.
Correct answer
C. 180°
Explanation
180° is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
B. Crookes Glass
Explanation
Crookes glass is a kind of glass which contains mainly cerium oxide and silica. The cerium oxide can sharply absorb the harmful UV rays coming from the sun.
Correct answer
C. L
Explanation
L is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
A. 1st to 5th orbit
Explanation
1st to 5th orbit is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
A. always negative
Explanation
always negative is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
C. Constant
Explanation
Constant is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
C. F/8
Explanation
F/8 is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
B. Dyne
Explanation
Dyne is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
D. Momentum is not conserved
Explanation
Momentum is not conserved is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
D. due to surface tension
Explanation
According to Archimedes principle and we can note that the amount of water displaced by a needle is lesser than the amount of water moved out by the needle (that is displacement of the needle). So the needle initially stays on the surface of the water and then sinks into the water. Surface tension is a contractive tendency of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in the floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects (e.g. water striders) to run on the water surface. This property is caused by cohesion of similar molecules, and is responsible for many of the behaviors of liquids.