Who discovered Photon?

• George Crum

• Albert Einstein

• Henry Cavendish

• Humphry Davy

Contact force is another name for .............

• Friction

• Magnetic force

• Electrostatic force

• Muscular force

The force of friction between two surfaces will increase if:

• a layer of lubricant is kept between the two surfaces

• the two surfaces are pressed harder

• air gap is created between the two surfaces

• irregularities on both the surfaces are removed

An image formed by a plane mirror, that cannot be obtained on a screen is called _______.

• Virtual Image

• Real Image

• Inverted Image

• Erect Image

The force exerted by a magnet is an example of ...............

• Non-contact force

• Muscular force

• Contact force

• Electrostatic force

According to the Second Law of Motion, for a given force, acceleration is inversely proportional to the _________ of an object.

• density

• volume

• force

• mass

The coil wire in the electric room heater or electric cooking heater is called ............

• circuit

• element

• filament

• cells

The passage of an electric current through a conducting liquid causes ............

• Galvanisation

• Evaporation

• Physical Reaction

• Chemical Reaction

189.

The incident ray, the _________ at the point of incidence and the reflected ray all lie in the same plane.

• surface

• tangent

• normal

• angle of reflection

During uniform motion of an object along a straight line, the ________ remains constant with time.

• time

• velocity

• acceleration

• distance