The speed of light is
330m/s
300,000,000m/s
30,000m/s
300,000,000km/s
At a particular time of a day the ratio of height of an object and the length of its shadow is 'x'.Using this calculate the height of a tree if the length of the shadow of tree is L
x/L
x * L
x+L
L-x
Which of the following statements is true?
A plane mirror some times froms an inverted image.
A concave mirror always forms a virtual,erect and diminished image.
A concave lens always forms a virtual,erect and diminished image.
All of these.
Which of the following is a reflector of light?
Sun
Moon
Star
Filament
Light:
light waves are longitudinal wave
requires a material medium to travel form one place to another
does not require a material medium
light has mass but it is negligible
Shadows are formed because :
opaque bodies allow the light to pass through them.
light can bend around the opaque bodies.
light rays cannot pass through the opaque bodies.
light shows the phenomenon of diffraction around large objects.
Translucent objects:
do not allow light to pass through them
allow light to pass through them
allow only a partial amount of light to pass through them
absorb all the light incident on them
Which of the following letters will be seen without any change in a plane mirror?
S
T
L
P
The distance between the sun and the earth is
150 million kilometers
100 million kilometers
2 billion kilometers
1.2 light years