Answer:
Hertz extended Maxwell's idea that light is produced by the interaction of electromagnetic fields. Waves produced a diffraction pattern. Results supported the wave theory of light.
Answer:
a) 42.52°
b) 63.98°
Explanation:
Refractive index of pipe = 1.48 = n₂
Refractive index of air = 1.0003 = n₁

∴ Minimum angle of incidence is 42.52°
Refractive index of water = 1.33 = n₁

∴ Minimum angle of incidence is 63.98°
The cells are called insibatss, I think I spelled that right but
A car speeds up on how its built
Answer:
The Amount of work is done on the box by the net force is 378 Joules.
Explanation:
Given:
A 42 N net force is applied to a box which slides horizontally across a floor.
Force = 42 N
Force applied for a displacement of 9.0 m
Displacement = 9.0 m
To Find:
Amount of work is done on the box by the net force = ?
i.e Work = ?
Solution:
When a force causes a object to move, work is being done on the object by the force. Work is the measure of energy transfer when a force (F) moves an object through a distance (d).
Formula is given by

Substituting the given values we get
∴ Work = 42 × 9.0
∴ Work = 378 N-m
or
∴ Work = 378 Joules
The Amount of work is done on the box by the net force is 378 Joules.