Answer:
A light beam incident on a diffraction grating consists of waves with two different wavelengths. The separation of the two first order lines is great if
the dispersion is great
Answer:
22.05 Kg
Explanation:
Apply the formula:
GPE = Gravity . Mass . ΔHigh
2778.3 = 10 . Mass . 12.6
2778.3 = 126 . Mass
Mass = 2778.3/126
Mass = 22.05
Answer:
a) 
b) 
Explanation:
Given:
String vibrates transversely fourth dynamic, thus n = 4
mass of the string, m = 13.7 g = 13.7 × 10⁻¹³ kg
Tension in the string, T = 8.39 N
Length of the string, L = 1.87 m
a) we know

where,
= wavelength
on substituting the values, we get

or

b) Speed of the wave (v) in the string is given as:

also,

equating both the formula for 'v' we get,

on substituting the values, we get

or

or

Answer:
the angular velocity of the carousel after the child has started running =

Explanation:
Given that
the mass of the child = m
The radius of the disc = R
moment of inertia I = 
change in time = 
By using the torque around the inertia ; we have:
T = I×∝
where
R×F = I × ∝
R×F =
∝
F =
∝
∝ =
( expression for angular angular acceleration)
The first equation of motion of rotating wheel can be expressed as :

where ;
∝ =
Then;


∴ the angular velocity of the carousel after the child has started running =
