All categories

3 years ago

Why are electromagnets more useful than permanent magnets in many

Physics

2 answers:

Likurg_2 [28]3 years ago

5 0

Answer: Electromagnets can be turned on and off by controlling the current

Explanation:

Tasya [4]3 years ago

5 0

B. By controlling the current, electromagnets can be turned on and off

You might be interested in

A way to charge insulators and conductors (the answer in 7 alphabets)

Fudgin [204]

Answer

RUBBING

Explanation:

3 0

3 years ago

When metals and nonmetals combined, first there is a complete transfer of charge to form cations and anions to complete their va

Llana [10]

<span> Then IONIC bonds are formed by electrostatic attraction.</span>

3 0

3 years ago

A mass of 0.34 kg is fixed to the end of a 1.4 m long string that is fixed at the other end. Initially at rest, he mass is made

frozen [14]

At time $t$ seconds, the mass has angular speed

$\omega = \left(3.31\dfrac{\rm rad}{\mathrm s^2}\right) t$

and hence linear speed

$v = (1.4\,\mathrm m) \omega = (1.4\,\mathrm m) \left(3.31\dfrac{\rm rad}{\mathrm s^2}\right) t$

After 8 s, its linear speed is

$v = (1.4\,\mathrm m) \left(3.31\dfrac{\rm rad}{\mathrm s^2}\right) (8\,\mathrm s) = 37.072 \dfrac{\rm m}{\rm s} \approx 37 \dfrac{\rm m}{\rm s}$

and has centripetal acceleration with magnitude

$a = \dfrac{v^2}{1.4\,\rm m} \approx 981.667\dfrac{\rm m}{\mathrm s^2} \approx 980 \dfrac{\rm m}{\mathrm s^2}$

To maintain this linear speed, by Newton's second law the required centripetal force should have magnitude

$F = (0.34\,\mathrm{kg}) a \approx 333.767\,\mathrm N \approx \boxed{330 \,\mathrm N}$

5 0

2 years ago

A dripping water faucet steadily releases drops 1.0 s apart. As these drops fall, does the distance between them increase, decre

ololo11 [35]

Answer:

Distance between them increase

Explanation:

The position S of the water droplet can be determined using equation of motion

$S=ut+\frac{1}{2} at^2$

where $u$ is the initial velocity which is zero here

$t$ is time taken, $a$ is acceleration due to gravity

the position of first drop after time $t$ is given by

$S_{1} =0 \times t+ \frac{1}{2} at^2=\frac{1}{2} at^2............(1)$

the position of next drop at same time is

$S_{2} =\frac{1}{2} a(t-1)^2 = \frac{1}{2} a(t^2+1-2t)............(2)$

distance between them is $S_{1} -S_{2}$ is $a(t-1)$

from the above the difference will increase with the time

3 0

3 years ago

What is the acceleration of a racing car if it's speed is increased uniformly from 44 m /s to 66 m / s over an 11 second period

jolli1 [7]

Answer:

the acceleration of the race car is 2 m/s²

Explanation:

Given;

initial velocity of the race car, u = 44 m/s

final velocity of the race car, v = 66 m/s

time of motion of the race car, t = 11 s

The acceleration of the race car is calculated as;

$a = \frac{v-u}{t} \\\\a = \frac{66-44}{11} \\\\a = 2 \ m/s^2$

Therefore, the acceleration of the race car is 2 m/s²

7 0

3 years ago