Tag: physics

Questions Related to physics

Choose the correct statements from the following $A.C.$ cannot be used in

physics alternating currents sinusoidal current types of current movement of charge

  1. Electroplating

  2. Charging a battery

  3. Charging a capacitor

  4. Electrolysis

  5. Heating a room

Show answer
Correct Option: A

Two alternating currents having value $I _{1} = 3\sin \omega t$ and $I _{2} = 4\sin \left (\dfrac {\pi}{2} - \omega \right )$ are superimposed and passed through a hot wire ammeter. Then the roading of ammeter will be

physics alternating currents sinusoidal current types of current movement of charge

  1. $5A$

  2. $-\dfrac {5}{\sqrt {2}}A$

  3. $7A$

  4. $\dfrac {7}{\sqrt {2}}A$

Show answer
Correct Option: C

In alternating current

physics alternating currents sinusoidal current types of current movement of charge

  1. The direction of current is always positive

  2. The direction of current is always negative

  3. The direction of current changes constantly

  4. The direction of current is either positive or negative

Show answer
Correct Option: C
Explanation:

C

Electric charge in alternating current (AC) changes direction periodically. The voltage in AC circuits also periodically reverses because the current changes direction.

 

An alternating current is that current which changes regularly its

physics alternating currents sinusoidal current types of current movement of charge

  1. Magnitude

  2. Direction

  3. Both a and b

  4. None of the above

Show answer
Correct Option: C

In an A.C. circuit a resistance R is connected in series with an inductance L.The phase difference between voltage and current is $45^o$. Then what will be the value of inductive reactance?

physics alternating currents sinusoidal current types of current movement of charge

  1. R

  2. $\frac{R}{2}$

  3. $\frac{R}{4}$

  4. 2R

Show answer
Correct Option: A

Screw is a modified :

physics common machines kinds of simple machines inclined plane, wedge, screw and wheel and axle types of simple machines

  1. Lever

  2. Gear

  3. Inclined plane

  4. Wheel

Show answer
Correct Option: C
Explanation:

A screw is a modification of an inclined plane . The threads of a screw are like an inclined plane wrapped around a cylinder.

A flat plank can be used as an inclined plane.

physics common machines kinds of simple machines inclined plane, wedge, screw and wheel and axle types of simple machines

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

If we raise an one end of plank than we can use it as inclined plane.

The staircase used by the airline passengers is a modified form of :

physics common machines kinds of simple machines inclined plane, wedge, screw and wheel and axle types of simple machines

  1. Lever

  2. Wedge

  3. Inclined plane

  4. Pulley

Show answer
Correct Option: C
Explanation:

The stair case used by the airline passengers is a modified form of inclined plane.

If the slope of an inclined plane increases then more effort is required to push a load up.

physics common machines kinds of simple machines inclined plane, wedge, screw and wheel and axle types of simple machines

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

As slope increases component of weight along inclined plane increases so more effort required to push a load up.

Distance between the successive threads of a screw is called :

physics common machines kinds of simple machines inclined plane, wedge, screw and wheel and axle types of simple machines

  1. Arm length

  2. Principle of screw

  3. Pitch of screw

  4. Least count

Show answer
Correct Option: C
Explanation:

Distance between the successive threads of screw is known as Pitch of screw.