1
Q:

A boy sitting in a train moving with a uniform velocity drops a coin outside. A man standing outside the train will find the trajectory of the coin to be

A) a parabola B) a circle
C) a horizontal straight line D) a vertical straight line

Answer:   A) a parabola

Explanation:

Parabola, because when the coin is dropped at a particular point, it has the same velocity as the running train. So by Newton's first law, it continues its motion horizontally with that velocity. But then, it is also pulled down by earth's gravity continuously. In this situation its horizontal motion gives way to the parabolic motion until it reaches the ground.

Subject: Physics
Q:

Which is best used as a sound absorbing material in partition walls ?

A) Stone chips B) Steel
C) Glass - wool D) Glass pieces
 
Answer & Explanation Answer: C) Glass - wool

Explanation:

Materials that do not transfer mechanical energy well. These tend to be soft,flexible, low density, and with high surface area to linear area ratios.

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Exam Prep: AIEEE

3 181
Q:

On which day ' National Science Day ' is celebrated in India ?

A) February 23 B) February 25
C) February 26 D) February 28
 
Answer & Explanation Answer: D) February 28

Explanation:

National Science Day is celebrated in India on 28 February each year to mark the discovery of the Raman effect by Indian physicist Sir Chandrashekhara Venkata Raman on 28 February 1928.

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Exam Prep: Bank Exams , CAT
Job Role: Bank Clerk

6 117
Q:

The capacity of a pure capacitor is 1 farad. In D.C circuit, its effective resistance will be

A) Zero B) Infinite
C) 1 Ohm D) 1/2 Ohm
 
Answer & Explanation Answer: B) Infinite

Explanation:
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4 432
Q:

A convex mirror is used to form an image of a real object. The image

A) is diminished in size B) is erect
C) always lies between the pole and the focus D) all of the above
 
Answer & Explanation Answer: D) all of the above

Explanation:
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5 266
Q:

The quality of sound produced by an instrument depends on the

A) Frequency B) Intensity
C) Number of overtones D) None of these
 
Answer & Explanation Answer: C) Number of overtones

Explanation:
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