Pretty please help yah girl out :)

In situation A, a bar magnet moves toward a stationary coil at a constant speed, and the maximum current is recorded. If the mag

slava [35]

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.

3 0

3 years ago

In a manufacturing process, a large, cylindrical roller is used to flatten material fed beneath it. The diameter of the roller i

kotykmax [81]

The maximum angular speed of the roller is 3.47rad/a,

the maximum tangential speed of the point an the rim of the roller is 1.47m/s,

the time t should the driven force be removed from the roller so that the roller does not reverse its direction of rotation is t = 2.78s,

5.4 rotation has the roller turned between t=0 and the time found in part c

<h3>What does tangential speed refer to?</h3>

Any item moving along a circular path has a linear component to its speed called tangential velocity. An object's velocity is always pointed tangentially when it travels in a circle at a distance r from the center. The word for this is tangential velocity.

To calculate the tangential speed, divide the circumference by the time required to complete one spin. For instance, if it takes 12 seconds to complete one rotation, divide 18.84 by 12 to get 1.57 feet per second as the tangential velocity.

(a) angular speed w = dθ/dt = 5t - 1.8t^2

dw/dt = 5 - 3.6t = 0 for max w

so max w occurs at t = 5/3.6 s = 1.39s

so w max = 5*1.39 - 1.8*(1.39)^2 = 3.47 rad/s

(b) tangential speed v = r*w

r = D/2 = 0.5m

so v = 0.5*w = 1.74 m/s

(c) w is positive until 5t = 1.8t^2

so t = 5/1.8s = 2.78s (or t = 0 invalid)

After t = 2.87s, w is negative (starts reversing direction of rotation)

Driving force would actually have to be removed some time before t=2.78s because the roller can't stop instantaneously, but insufficient info to calculate this.

(d) Up to t = 2.78s, θ = 2.5*(2.78)^2 - 0.6*(2.78)^3 rad = 33.95 rad = 5.40 rotations

Therefore,

A) 3.47rad/a

B) 1.47m/s

C) t = 2.78s

D) 5.4 rotation

To learn more about tangential speed, refer to:

brainly.com/question/19660334

#SPJ4

4 0

2 years ago

I have three questions. John has to hit a bottle with a ball to win a prize. He throws a 0.4 kg ball with a velocity of 18 m/s.

AfilCa [17]

1. 5.5 m/s

We can solve the problem by applying the law of conservation of momentum. The total momentum before the collision must be equal to the total momentum after the collision, so we have:

$m_1 u_1 + m_2 u_2 = m_1 v_1 + m_2 v_2$

where

m1 = 0.4 kg is the mass of the ball

u1 = 18 m/s is the initial velocity of the ball

m2 = 0.2 kg is the mass of the bottle

u2 = 0 is the initial velocity of the bottle (which is initially at rest)

v1 = ? is the final velocity of the ball

v2 = 25 m/s is the final velocity of the bottle

Substituting and re-arranging the equation, we can find the final velocity of the ball:

$v_1 = \frac{m_1 u_1 - m_2 v_2}{m_1}=\frac{(0.4 kg)(18m/s)-(0.2 kg)(25 m/s)}{0.4 kg}=5.5 m/s$

2. 22.2 m/s

We can solve the problem again by using the law of conservation of momentum; the only difference in this case is that the bullet and the block, after the collision, travel together at the same speed v. So we can write:

$m_1 u_1 + m_2 u_2 = (m_1 +m_2) v$