Physics Test - ...

The rms value of an ac current of \(50 \mathrm{~Hz}\) is \(10 \mathrm{amp} .\) The time taken by the alternating current in reaching from zero to maximum value and the peak value of current will be:

In a p-n-p transistor, working as a common base amplifier, the current gain is \(0.96\) and the emitter current is \(7.2\) mA. The base current is:

What is the direction of force of friction acting on a body moving on a fixed surface?

A point charge \(+10 \mu C\) is at a distance of \(5 cm\) directly above the centre of a square of side \(10 cm\), as shown in Figure. What is the magnitude of the electric flux through the square? (Hint: Think of the square as one face of a cube with edge \(10 cm\) ).

Which of the following does not affect the apparent frequency in doppler effect?

A man of height \('h'\) walks along a straight path towards a lamp post of height \(H\) with a uniform velocity \('u'\). The velocity of the edge of the shadow on the ground will be:

What is the emissive power of sun when its temperature is doubled?

In an n-type silicon, which of the following statement is true:

The instantaneous voltage across a pure resistor is ______ with current.