Answer:
120 m
Explanation:
Given:
wavelength 'λ' = 2.4m
pulse width 'τ'= 100T ('T' is the time of one oscillation)
The below inequality express the range of distances to an object that radar can detect
τc/2 < x < Tc/2 ---->eq(1)
Where, τc/2 is the shortest distance
First we'll calculate Frequency 'f' in order to determine time of one oscillation 'T'
f = c/λ (c= speed of light i.e 3 x 
m/s)
f= 3 x / 2.4
f=1.25 x hz.
As, T= 1/f
time of one oscillation T= 1/1.25 x
T= 8 x 
s
It was given that pulse width 'τ'= 100T
τ= 100 x 8 x => 800 x s
From eq(1), we can conclude that the shortest distance to an object that this radar can detect:
= τc/2 => (800 x x 3 x )/2
=120m
Answer:
Magnetic energy and electromagnetic energy form of potential energy followed by a form of kinetic energy.
(B) is correct option.
Explanation:
Given that,
Lists a form of potential energy followed by a form of kinetic energy
We know that,
Sound energy :
The movement of energy through object it is called sound energy. When a object produced vibration by force then it moves in wave.
Sound wave is example of kinetic energy.
Nuclear energy :
The store energy in the nucleus of the atom it is called nuclear energy. This energy released when occurs fusion and fission.
Nuclear energy is the example of potential energy
Magnetic energy :
Magnetic energy is a type of potential energy which is depend on distance and position in the magnetic field.
Electromagnetic energy :
Electromagnetic energy is light energy. it is type of kinetic energy.
Gravitational energy :
Gravitational energy is a type of potential energy. It is an energy related with gravity or gravitational force.
Elastic energy :
The store energy in elastic object it is called elastic energy. This energy is a type of potential energy.
Electrical energy :
The movement of electrons is called electrical energy. When electrons move through a wire then it is are called electricity. Electrical energy is type of kinetic energy.
Hence, Magnetic energy and electromagnetic energy form of potential energy followed by a form of kinetic energy.
(B) is correct option.
Answer:
40m
Explanation:
let's calculate the acceleration first
force = mass × acceleration
rearranging to find acceleration:
acceleration = force ÷ mass
force = 25N, mass = 5.0kg
acceleration = 25 ÷ 5 = 5ms^-2
we can now use the formula v^2 = u^2 + 2as where v = final velocity, u = initial velocity, a = acceleration and s = distance
rearranging v^2 = u^2 + 2as the distance is
s = (v^2 - u^2) ÷ 2a
v = 20, u = 0, a = 5
s = (20^2 - 0^2) ÷ (2 × 5) = 40m
the distance is 40m
