For this question we should apply
a = v^2 - u^2 by t
a = 69 - 0 by 4.5
a = 69 by 4.5
a = 15.33
a = 6.85 m/s^2
If the answer in option is near to answer then , you can mark it as correct.
.:. The acceleration is 6.9 m/s^2
Answer:
Visible light
X rays
ultraviolet radiation
gamma rays
microwave radiation
Explanation:
Electromagnetic waves consist of oscillating electric and magnetic fields which vibrate in a direction perpendicular to the direction of motion of the wave (transverse wave). Electromagnetic waves have all same speed in a vacuum (
, known as speed of light) and are classified into 7 different types according to their frequency and wavelength. This classification is called electromagnetic spectrum.
From lowest to highest wavelength, the 7 types are:
Gamma rays
X-rays
Ultraviolet radiation
Visible light
Infrared radiation
Microwaves
Radio waves
Sound waves, on the contrary, do not belong to the electromagnetic spectrum, since they are another type of wave called mechanical waves (which consist of vibrations of the particles in a medium).
Answer:
The observer detects light of wavelength is 115 nm.
(b) is correct option
Explanation:
Given that,
Wavelength of source = 500 nm
Velocity = 0.90 c
We need to calculate the wavelength of observer
Using Doppler effect

Where, 


Hence, The observer detects light of wavelength is 115 nm.
As Potential energy =mgh
m= 0.95kg
h=3 meter
g = 9.8 m/sec^2. ( acceleration due to gravity)
So P.E =(0.95)(9.8)(3)kgm^2/s^2
P.E =27.93 joules