Answer:
D and A
Explanation:
Hint The basic difference between them is that a bar magnet is a permanent magnet whereas an electromagnet is a temporary magnet. An electromagnet is formed when an electric current is passed through wires wound around soft metalcore. An electromagnet loses its magnetism once the current flow is stopped.
Answer:
(a) T = 0.015 N
(b) M = 1.53 x 10⁻³ kg = 1.53 g
Explanation:
(a) T = 0.015 N
First, we will find the speed of waves:

where,
v = speed of wave = ?
f = frequency = 120 Hz
λ = wavelength = 6 cm = 0.06 m
Therefore,
v = (120 Hz)(0.06 m)
v = 7.2 m/s
Now, we will find the linear mass density of the coil:

where,
μ = linear mass density = ?
m = mass = 1.45 g = 1.45 x 10⁻³ kg
l = length = 5 m
Thereforre,

Now, for the tension we use the formula:

<u>T = 0.015 N</u>
<u></u>
(b)
The mass to be hung is:

<u>M = 1.53 x 10⁻³ kg = 1.53 g</u>
Rate of speed (3 m/s north is three miles per second north, so it's a rate of speed)
1.46m/s²
Explanation:
Given parameters:
Mass of cart = 281kg
Net external force = 411N
Unknown:
Acceleration of the cart = ?
Solution:
According to newton's second law " the net force on a car is the product of its mass and acceleration";
Force = mass x acceleration
Since acceleration of the cart is unknown;
Acceleration =
= 
Acceleration = 1.46m/s²
learn more:
Newton's laws brainly.com/question/11411375
#learnwithBrainly