Answer:
B.the same as Lily's.
Explanation:
When a disc is rotating on its axis uniformly with some angular velocity , every particle on it rotates with the same angular velocity , because every particle on it completes a rotation simultaneously . So in one rotation they take same time . Hence particles whether on the outer edge or near the axis , all have same angular velocity .
They but differ due to their different linear velocity . Linear velocity of particle near outer edge have greater magnitude. .
Answer: a dark (absorption) line
Explanation:
This is as a result of absorption of electromagnetic a specific wavelength. The pattern followed by such lines is characteristic of specific atoms in the path of radiation.
Answer:
The specific kinetic energy of a mass is 0.8 kJ/kg
Explanation:
Given that,
Velocity = 40 m/s
Specific kinetic energy is the kinetic energy per unit mass.
We need to calculate the specific kinetic energy
Using formula of specific kinetic energy


Put the value into the formula


We know that,
1 kJ = 1000 J
or, 1J=0.001 KJ
The specific energy is


Hence, The specific kinetic energy of a mass is 0.8 kJ/kg
Because we can send high voltage, low current which is more efficient since large amounts of current in the line causes power inefficiencies. AC can be transformed locally to high current lower voltage