Answer:
Mechanical waves
Explanation:
Waves are periodic oscillations, that carry energy, but not matter.
Waves are classified into two types:
- Mechanical waves: these waves are produced by the oscillations of the particles in a medium, which can oscillate along the direction of propagation of the wave (longitudinal wave) or perpendicular to the direction of motion of the wave (transverse wave). These waves can only propagate in a medium, so they cannot travel in a vacuum. Examples of mechanical waves are sound waves.
- Electromagnetic waves: these waves are produced by the oscillations of electric and magnetic field. They are transverse waves. They are the only type of wave able to propagate through a vacuum (so, through space).
Therefore, the waves that need molecules in order to transfer energy are mechanical waves.
Comets.
Small fragments of meteors, formed by ice and rock mixed consitute the comets.
Explanation:
Since it is mentioned that the block is in equilibrium, this means the resultant force is zero, and all the forces cancel out each other.
You have to think it in a way so that, the forward force cancel out the backward force. Check the picture attached, on the forward side,
3N + 5N = 8N which cancel out the backward force of 8N
Answer:
51 dioptre
Explanation:
u = Object distance = 2 cm
v = Image distance = 1 m
f = Focal length
Lens Equation
Power of lens
Power of the eye lens is 51 dioptre.
Answer:
See below
Explanation:
East components are 10 and 12 cos 30 = 20.392 m/s
North component = 12 sin 30 = 6 m/s
Resultant velocity = sqrt ( 20.392^2 + 6^2) = <u>21.26 m/s </u>
direction arc tan (6/20.392) = <u>16.4 degrees N of east </u>
