Answer:
Explained
Explanation:
Michelson contrast is used for patterns where the distribution of bright and dark segments is nearly equal.
It is given by:

where I_max = maximum illumination and I_min = minimum illumination
we know that
typically, I_min = 54% of I_max (general standard)
or I_min = 0.54 I_max
putting this value in above equation to get m
this approximately corresponds to m = 0.3 or 30%
hence, 30% recommended as the minimum Michelson contrast
The reversing of the magnet polarity will explain the different current reading.
Answer: Option D
<u>Explanation:</u>
According to Faraday's law of inductance, whenever a bar magnet is moved toward a stationary coil at constant speed, current will be generated in that coil. So in this case, the first maximum current in the above situation say A is recorded successfully.
Similarly, when the arrangement is kept as it is, in situation B, the current is observed to have different reading. This may be because of the polarity of the magnet would have changed leading to different current reading.
Answer:
7.15 m/s
Explanation:
We use a frame of reference in which the origin is at the point where the trucck passed the car and that moment is t=0. The X axis of the frame of reference is in the direction the vehicles move.
The truck moves at constant speed, we can use the equation for position under constant speed:
Xt = X0 + v*t
The car is accelerating with constant acceleration, we can use this equation
Xc = X0 + V0*t + 1/2*a*t^2
We know that both vehicles will meet again at x = 578
Replacing this in the equation of the truck:
578 = 24 * t
We get the time when the car passes the truck
t = 578 / 24 = 24.08 s
Before replacing the values on the car equation, we rearrange it:
Xc = X0 + V0*t + 1/2*a*t^2
V0*t = Xc - 1/2*a*t^2
V0 = (Xc - 1/2*a*t^2)/t
Now we replace
V0 = (578 - 1/2*1.4*24.08^2) / 24.08 = 7.15 m/s
Answer:
Potential energy = work done on the spring
= Force x displacement
= 15 N x 0.025 m
= 0.375 J