Answer:
A. friction is greatly reduced.
Explanation:
Maglev train runs on the principle of repulsion force due to magnetic field
here we know that magnetic field will apply force on the train which helps to levitate train in air
This is why it runs forward due to other component of magnetic force and hence it can run with high speed in air with least friction as there is no two surfaces in contact with each other
So here we can say that
Train run with very high speed due to least value of friction between two surfaces which moves relative to each other
so correct answer is
A. friction is greatly reduced.
<u>Answer:</u>
3.5 x 10^-8 J
<u>Explanation:</u>
We are given,
force experienced by a charge = 3.6 x 10^-4 N; and
distance of charge from the source of electric field = 9.8 x 10^-5 m
We know that, <em>Energy = force x distance</em>
therefore, to find the potential energy of the charge, we need to multiply its applied force with the given distance to get:
Electric potential energy of a charge = (3.6 x 10^-4) × (9.8 x 10^-5) = 3.5 x 10^-8 J
Therefore, the potential energy of a charge is 3.5 x 10^-8 J.
Answer:
-0.020475 V
Explanation:
= Vacuum permeability = 
= Number of turns of coil = 25
= Number of turns of coil 2 = 300
= Rate of current increased = 
d = Diameter = 2 cm
r = Radius = 
A = Area = 
Magnetic field in the solenoid is given by
Magnetic flux is given by
The average magnetic flux through each turn of the inner solenoid is
Mutual inductance is given by
The mutual inductance of the two solenoids is
Induced emf is given by
The emf induced in the outer solenoid by the changing current in the inner solenoid is -0.020475 V
Answer:
Explanation:
a. Landing height is
H=1.3m
Velocity of lander relative to the earth is, i.e this is the initial velocity of the spacecraft
u=1.3m/s
Velocity of lander at impact, i.e final velocity is needed
v=?
The acceleration due to gravity is 0.4 times that of the one on earth,
Then, g on earth is approximately 9.81m/s²
Then, g on Mars is
g=0.4×9.81=3.924m/s²
Then using equation of motion for a free fall body
v²=u²+2gH
v²=1.3²+2×3.924×1.3
v²=1.69+10.2024
v²=11.8924
v=√11.8924
v=3.45m/s
The impact velocity of the spacecraft is 3.45m/s
b. For a lunar module, the safe velocity landing is 3m/s
v=3m/s.
Given that the initial velocity is 1.2m/s²
We already know acceleration due to gravity on Mars is g=3.924m/s²
The we need to know the maximum height to have a safe velocity of 3m/s
Then using equation of motion
v²=u²+2gH
3²=1.2²+2×3.924H
9=1.44+7.848H
9-1.44=7.848H
7.56=7.848H
H=7.56/7.848
H=0.963m
The the maximum safe landing height to obtain a final landing velocity of 3m/s is 0.963m
Answer:
6.8 mm
Explanation:
We are given that
Mass of block,m=10 kg
Mass of bullet,
1 kg=1000 g
Total mass of system,M=
Speed of bullet,u=300 m/s
By law of conservation of momentum
According to law of conservation of energy
Change in kinetic energy of system=Change in potential energy of system
Where 
1m=100 cm
Distance traveled by block=
1cm=10 mm
