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Angle of incidence for a ray incident perpendicular to the mirror is_________

Since angle of incidence is defined as the angle between incident ray and normal at the point of incidence, the angle of incidence in this case is 0°.... View Article

Water is used to cool radiators of engines, because

Due to large specific heat of water, it releases large heat with very small temperature change.... View Article

A uniformly accelerating body covers a distance of 10 m in the 3rd second and 16 m in the 6th second. What is the initial velocity and acceleration?

s = ut + (at2/2) Equation 1 : 10 = u + (5a/2) Equation 2 : 16 = u + (11a/2) Solving Equation 1 and 2 we get, a = 2 m/s2 Putting the value of... View Article

In the image formed by a plane mirror the left of the object appears on the right and the right appears on the left, this is known as

In the image formed by a plane mirror the left of the object appears on the right and the right appears on the left, this is known as lateral... View Article

Choose the statements which state laws of reflection correctly? Statement 1: Angle of incidence is greater than the angle of reflection Statement 2: Angle of incidence is less than the angle of reflection Statement 3: Angle of incidence is equal to the angle of reflection Statement 4: The incident ray, the normal at point of incidence and the reflected ray all lie in the same plane.

The first law of reflection states that the angle of incidence is equal to the angle of reflection. And the second law states that the incident... View Article

What is the net force if two forces are acting in opposite directions on an object ?

If an object has two forces acting on it with equal size but with opposite diversity, the net force will be zero (null vector)... View Article

Weight of an object has S.I. unit of :

The unit of weight is the same as that of force, ie., Newton(N) Weight is the measure of the force of gravity acting on a body. The formula for... View Article

The angle between the normal at point of incidence and the incident ray is known as?

The angle between the normal at point of incidence and the incident ray is known as the angle of incidence.... View Article

If P is an illuminating point source and the arrows depicts the direction of north, south, west and east. Then in which directions will the illuminating source emit light?

Sun emits its light rays in all directions. Similarly all light sources will emit equal amount of light in all directions.... View Article

What is the Main Constituent of LPG?

Liquefied petroleum gas, or commonly referred to as LPG is a flammable mixture of hydrocarbon gases that are used as fuel in heating appliances... View Article

Between the plates of a parallel plate capacitora dielectric plate is introduced just to fill the space between the plates. The capacitor is charged and later disconnected from the battery. The dielectric plate is slowly drawn out of the capacitor parallel to the plates. The plot of the potential difference across the plates and the length of the dielectric plate drawn out is [MP PET 1997]

While drawing the dielectric plate outside, the capacitance decreases till the entire plate comes out and then becomes constant. So, V increases... View Article

Choose the right answer from the following

How can we decrease the capacitance of a parallel-plate capacitor? Increasing the stored charge in the capacitor Decreasing the stored... View Article

If the speed of light in air is 3*108 m/s and speed of light in water is reduced by a factor of 1.3 when compared with that of speed of light in air. Find out the speed of light in water?

The speed of light in water is reduced by a factor of 1.33. i.e. Speed of light in water is 3*108/1.33 = 2.87*108 m/s.... View Article

Threecapacitors are connected to DC source of 10volts shown in the adjoining figure. If the charge accumulated on plates of C1,C2 and C3 are respectively, then [CPMT 1986]

In series combination, charge is same on each capacitor.... View Article

A graph is plotted between angle ofdeviation (d) and angle of incidence (i) for a prism. The nearly correct graph is

For a prism, as the angle of incidence increases, the angle of deviation first decreases, goes to a minimum value and then increases.... View Article

A lead bullet of mass 2 Kg, travelling with a velocity of 20 m/s, comes to rest after penetrating 20m in a still target. Find the resistive force applied by the target and acceleration of the bullet.

We know that, v2 = u2 – 2 as v = 0 m/s u = 20 m/s, s = 20m Acceleration = 40 m/s2 So, F = - ma (resistive force) F = - 80 N... View Article

A parallel plate capacitor is made by stacking equally spaced plates connected alternately. If the capacitance between any two plates is then the resultant capacitance is [NCERT 1971; DPMT 2001; MP PMT 2003; AIEEE 2005]

The givenarrangement becomes an arrangement of (n-1) capacitors connected in parallel. So CR=(n-1)C... View Article

Choose the correct statements: Statement 1: We see objects, when light emitted from the objects enter our eyes Statement 2: We see objects, when light reflected from the objects enter our eyes Statement 3: Eyes alone cannot see an object Statement 4: Eyes emit light rays in all direction

We see objects, when light emitted from the objects enter our eyes but eyes alone cannot see an object... View Article

What is light?

Answer: Light is an electromagnetic wave emitted by hot objects like lasers, bulbs, and the sun. Light is a type of kinetic energy that allows... View Article

In a compound microscope, if the objectiveproduces an image Io and the eye piece produces an image Ie, then [MP PET 1990]

In compound microscope objective forms real image while eye piece forms virtual image.... View Article

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