Answer:
The speed of cart B is 11.21 m/s.
Explanation:
Given that,
Speed of cart A = 9.25 m/s
Speed of cart B = 7.15 m/s
Mass of cart A = 72.0 kg
Mass of cart B = 55.0 kg
Speed of card A after collision = 6.15 m/s
We need to calculate the speed of cart B
Using conservation of momentum

Put the value into the formula



Hence, The speed of cart B is 11.21 m/s.
B = 0.018 T Ans,
Since, it is moving in a circular path, thus, centripetal force will act on it i.e.
F =

where, m is the mass of the object, v is the velocity and r is the radius of circular path.
And, since a positive charge is moving, it will create magnetic force which is equal to F = qvB
where q is the charge, v is the velocity of the particle and B is the magnetic field.
Now, the two forces will be equal,
i.e.

= qvB
⇒

= qB
⇒B =

<span>putting the values, we get,
</span>
use q = 1.6 * 10^ -19
⇒ B = 0.018 T
The net force required to accelerate a car is 6000 N.
Force is defined as the product of the mass and acceleration of the body. Force is used to changing the velocity that is to accelerate an object or a body of a particular mass. The unit of Force is Newton or kg m/s^2.
The formula used to calculate the net force is :
F = ma
where, F = Force
m = mass = 2000 kg
a = acceleration = 3.00 m/s^2
∴ F = 2000*3
F = 6000 N
Thus, to accelerate the car at 3.00 m/s^2 of mass 2000 kg net force required is 6000 N.
To learn more about force,
brainly.com/question/1046166
The stopwatch will be the most useful in determining the kinetic energy of a 50 g battery- powered car traveling a distance of 10 m.
<h3>What is kinetic energy?</h3>
Kinetic energy is the energy of a body possessed due to motion.
This means that for an object to possess kinetic energy, it must be in motion.
The kinetic energy is measured in Joules, which is a product of the mass of the substance and the time taken to travel a distance.
A stopwatch is an instrument used to measure time as one of the components of kinetic energy.
Therefore, the stopwatch will be the most useful in determining the kinetic energy of a 50 g battery- powered car traveling a distance of 10 m.
Learn more about kinetic energy at: brainly.com/question/12669551
Keep cool by being active at night, whereas some other desert animals get away from the sun's heat by digging underground burrows.