NDA PHYSICS QUIZ

Question 1:

The signal is used for which electrical circuit ?

rheostat

resistance

wire joint

electric cell

Question 2:

Select the false statement with reference to the frequency range of sound

The range of audible waveform in different organisms is different.

The probability of an earthquake is detected on the basis of the infrared wave.

Ultrasonic waves travel along a definite path even in the presence of obstacles.

None of these.

Question 3:

When light waves travel from air to glass, which variables are affected ?

Wavelength, frequency and velocity

Velocity and frequency only

Wavelength and frequency only

Wavelength and velocity only

Question 4:

A mirror used for rear-view on an automobile has a radius of curvature of 2.00 m. If a car is located at 4.00 m from this mirror. The nature of the image is –

Virtual, inverted, and diminished

Real, inverted, and diminished

Virtual, erect, and diminished

Virtual, erect, and magnified

Question 5:

Which of the following statements is correct?

The focal length of a convex lens is shorter for blue light than for red.

The focal length of a convex lens is equal for blue light than for red.

The focal length of a convex lens is longer for blue light than for red.

The focal length of a convex lens is maximum for yellow light.

Question 6:

With reference to alternating current and direct current, consider the following statements-

Rectifier is used to convert DC to AC.
Frequency of direct current is infinity.
Conversion of AC to DC is done using a rectifier.
AC can be produced by using a device called alternator.

Which of the following statements is/are incorrect?

3 and 4 only

2 only

1 and 2 only

2, 3, and 4 only

Question 7:

Which of the following is not correctly matched?

Density - $\left[M L^{-3}\right]$

Frequency - $\left[M^0 L^0 T^{-1}\right]$

Angular momentum $-\left[M^0 L T^{-1}\right]$

Acceleration - $\left[M^0 L T^{-2}\right]$

Question 8:

If an object vibrates with 2000 Hz, then what will be the time period of the oscillation?

0.002 sec.

0.0005 sec.

0.0002 sec.

2000 sec.

Question 9:

Which of the following instruments transform heat energy into kinetic energy ?

Electric motor

Steam engine

Electric bulb

Solar cell

Question 10:

The sink temperature of a Carnot heat engine is 30 °C and the efficiency is 40%. Find the temperature of heat source of the engine?

$615 \mathrm{~K}$

$750 \mathrm{~K}$

$550 \mathrm{~K}$

$505 K$