Answer:
B = 0.126 T
Explanation:
As per Faraday's law we know that rate of change in magnetic flux will induce EMF in the coil
So here we can say that EMF induced in the coil is given as

initially the coil area is perpendicular to the magnetic field
and after one fourth rotation of coil the area vector of coil will be turned by 90 degree
so we can say


now we will have



Answer:
Option D.) 0.09 I₀
Explanation:
The intensity, I, of a polarized light after passing through a polarizing filter is given by
Original Intensity
Angle between the direction of polarization and the axis of filter
After passing through the first polarizer, the initial intensity,
is halved, i.e 
After passing through the second polarizer, the angle of polarization, θ = 30⁰


After passing through the third polarizer, the angle of polarization, θ = 90⁰-30⁰ = 60⁰



Answer:
I would increase the horizontal velocity or the vertical velocity or both to make the ball go the extra distance to cross the goal line.
Explanation:
In order to increase the horizontal distance covered by the ball, we need to examine the variables involved in the formula of range of projectile. The formula for the range of projectile is given as follows:
R = V₀² Sin 2θ/g
where, g is a constant on earth (acceleration due to gravity) and θ is the angle of ball with ground at the time of launching. The value of θ should be 45° for maximum range. In this case we do not know the angle so, we can not tell if we should change it or not.
The only parameter here which we can increase to increase the range is launch velocity (V₀). The formula for V₀ in terms of horizontal and vertical components is as follows:
V₀ = √(V₀ₓ² + V₀y²)
where,
V₀ₓ = Horizontal Velocity
V₀y = Vertical Velocity
Hence, it is clear from the formula that we can increase both the horizontal and vertical velocity to increase the initial speed which in turn increases the horizontal distance covered by the ball.
<u>Therefore, I would increase the horizontal velocity or the vertical velocity or both to make the ball go the extra distance to cross the goal line.</u>
Answer:
0.25 m/s
Explanation:
This problem can be solved by using the law of conservation of momentum - the total momentum of the squid-water system must be conserved.
Initially, the squid and the water are at rest, so the total momentum is zero:

After the squid ejects the water, the total momentum is

where
is the mass of the squid
is the velocity of the squid
is the mass of the water
is the velocity of the water
Due to the conservation of momentum,

so

so we can find the final velocity of the squid:

and the negative sign means the direction is opposite to that of the water.