Answer:
E_{k2}=2660 [J] kinetic energy.
Explanation:
The energy in the initial state i.e. when the rollercoaster is at the top is equal to the energy in the final state i.e. when it is at the bottom of the hill.
These states can be represented by means of the second equation.
![E_{k1}+E_{p1}=E_{k2}\\160 + 2500 = E_{k2}\\E_{k2}=2660 [J]](https://tex.z-dn.net/?f=E_%7Bk1%7D%2BE_%7Bp1%7D%3DE_%7Bk2%7D%5C%5C160%20%2B%202500%20%3D%20E_%7Bk2%7D%5C%5CE_%7Bk2%7D%3D2660%20%5BJ%5D)
Since the rollercoaster is located in the bottom of the hill where the potential energy level is zero, therefore there is only kinetic energy in the second state.
Answer:
C. A baseball bat strikes a baseball.
Explanation:
Newton's second law of motion states that acceleration happens when force is applied on the mass.
<em>A baseball bat strikes a baseball is the best example of Newton's second law of motion because acceleration of the baseball is directly proportional to the force by which baseball bat hit it.</em>
Hence, the correct option is 'C. A baseball bat strikes a baseball.'
Just treat the bead as a point charge.
E = kq/r^2, and E points away from the center of the sphere since the charge is positive.
<h2>
Answer:</h2>
0.31425 Tesla
<h2>
Explanation:</h2>
The magnetic field strength of a solenoid can be found by using the Ampere's law as follows;
BL = μ₀ x N x I -------------------(i)
Where;
B = magnetic field strength
L = length of the solenoid
μ₀ = magnetic constant = 1.257 x 10⁻⁶H/m
N = number of turns in the coil of the solenoid
I = current flowing through the coil of the solenoid.
<em>From the question, </em>
L = 20cm = 0.2m
N = 5000 turns
I = 10A
<em>Substitute these values into equation (i) as follows;</em>
B x 0.2 = 1.257 x 10⁻⁶ x 5000 x 10
0.2B = 6.285 x 10⁻²
<em>Solve for B;</em>
B = 6.285 x 10⁻² / 0.2
B = 31.425 x 10⁻²
B = 0.31425 T
Therefore, the magnetic field strength is 0.31425 Tesla
