Discussions on certain questions.

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The discussion centers on two exam questions regarding physics concepts. In the first question, participants debate the correct measurement associated with volts, with suggestions that "electromagnetic force" may be a typo for "electromotive force," and some argue for potential difference as work done per unit charge. The second question prompts disagreement over statements about velocity and acceleration, with participants asserting that options B and D are false due to the definitions of speed and velocity. The consensus indicates that speed's variability directly affects velocity, challenging the accuracy of the exam's wording. Overall, the discussion raises concerns about the clarity and correctness of the exam questions.
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Q. No. 1. If Watt measures power, what does volt measure?

A. Electrical current

B. Energy

C. Electromagnetic force

D. Electrical resistance


Q.No. 2. Which of the following statements is false?

A. A body can have zero velocity and still be accelerated

B. A body can have a constant velocity and a varying speed

C. A body can have a constant speed and a varying velocity

D. The direction of the velocity of a body can change when
its acceleration is constant.

These questions were asked in an exam. The examiner says if you have any objection to these questions, you are allowed to raise it.
 
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chandra.phys said:
Q. No. 1. If Watt measures power, what does volt measure?

A. Electrical current

B. Energy

C. Electromagnetic force

D. Electrical resistance

None of the above! :confused:
 
Should I assume electromagnetic force is a typing error for electromotive force, and choose C.
Or should i say potential difference is work done on a unit charge in moving it from one point to another. This work is stored as potential energy. So, this leads to choice B.
Or should i raise my objection to the examiner that the question is wrong?
 
in the second question B is false because speed is the magnitude of velocity , and as the magnitude changes , the vector changes
in D , A = dV/dt
or the change in velocity over the change in time
if the change in time is constant , but velocity is changing then surely acceleration will change
velocity is a vector , it depends on the magnitude which is the speed , and the direction of that speed , if you change the direction , the velocity vector changes , thus leading to a change in acceleration ,
so both B and D are incorrect in my opinion , if i am wrong , i hope someone would correct me
 
In Q no. 1, B is the false statement. The magnitude of velocity is speed. if speed varies obviously, the velocity has to vary.
 
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