Practicle Physics

What is the primary purpose of a rheostat?

• • Temperature measurement

  
  

• Controlling electrical resistance

• Generating magnetic fields

• Transmitting radio waves

Which condition is necessary for observing Newton's rings?

• White light source

• Polarized light source

• • Monochromatic light source

  
  

• Incoherent light sourc

What is the cause of the formation of Newton's rings?

• 
  

• Reflection of light

• Refraction of light

• Interference of light

• Diffraction of light

How does a polarimeter measure specific rotation?

• By detecting absorbance

• By analyzing color changes

• By measuring light intensity

• By determining the angle of optical rotation

What happens to the angle of diffraction when the wavelength of light increases in a grating experiment?

• Increases

• Decreases

• Remains constant

• Becomes unpredictable

If the temperature of a blackbody is doubled according to Stefan's Law, what happens to the radiated power

• It remains constant

• It is halved

• It doubles

• It quadruples

What is specific resistance, also known as resistivity

• The resistance of a material per unit volume

• The resistance of a material per unit length

• The reciprocal of resistance

• The resistance of a material per unit area

What is the primary direction of the Earth's magnetic field at the geographic North Pole

• North to South

• South to North

• East to West

• West to East

How does a potentiometer assist in the calibration of an instrument?

• By generating magnetic fields

• By adjusting resistance

• By measuring temperature

• By changing color

In practical applications, why is it important to understand and manipulate the energy band gap of semiconductors?

• To control electrical conductivity

• To influence optical properties

• To enhance electronic device performance

• All of the above