Ask question

Ask question

All categories

3241004551 [841]

3 years ago

5

which of the following are good conductors under normal conditions? A. Penny B.copper wire C. a dime D.plastic E.aluminum foil F

.water

2 answers:

Anvisha [2.4K]3 years ago

5 0

Answer:

see explanation

Explanation:

A,B,C,E

professor190 [17]3 years ago

3 0

B.

Because its copper

You might be interested in

1) A car is moving to the right with the constant speed of 1.2 m/s. If the car starts

Marina CMI [18]

(100, 108)
Due to
1.2x90=108

100, 108

7 0

3 years ago

If the atmosphere is like a greenhouse, what parts of it function as the glass

prohojiy [21]

The ozone layer is like the glass. the light from the sun enters the atmosphere and when the heat bounces back it is hard to escape the ozone layer therefore the earth's temperature rises

5 0

3 years ago

Read 2 more answers

If a wave is traveling at 60cm/second and has a wavelength of 15 cm what is the frequency?

REY [17]

The frequency of the wave is 4 Hz

4 0

3 years ago

The heating element in a kettle behaves like a resistor. A particular kettle needs to operate at 230 V, with a power of 1500 W.

dedylja [7]

Answer:

R = 35.27 Ohms

Explanation:

Given the following data;

Voltage = 230V

Power = 1500W

To find the resistance, R;

Power = V²/R

Where:

V is the voltage measured in volts.

R is the resistance measured in ohms.

Substituting into the equation, we have;

1500 = 230²/R

Cross-multiplying, we have;

1500R = 52900

R = 52900/1500

R = 35.27 Ohms.

Therefore, the resistance which the heating element needs to have is 35.27 Ohms.

4 0

3 years ago

To meet a U.S. Postal Service requirement, employees' footwear must have a coefficient of static friction of 0.5 or more on a sp

motikmotik

Answer:

0.79 s

Explanation:

We have to calculate the employee acceleration, in order to know the minimum time. According to Newton's second law:

$\sum F_x:f_{max}=ma_x\\\sum F_y:N-mg=0$

The frictional force is maximum since the employee has to apply a maximum force to spend the minimum time. In y axis the employee's acceleration is zero, so the net force is zero. Recall that $f_{max}=\mu N$

Now, we find the acceleration:

$\mu N=ma_x\\\mu mg=ma_x\\a_x=\mu g\\a_x=0.83(9.8\frac{m}{s^2})\\a_x=8.134\frac{m}{s^2}$

Finally, using an uniformly accelerated motion formula, we can calculate the minimum time. The employee starts at rest, thus his initial speed is zero:

$x=v_0t+\frac{1}{2}a_xt^2\\2x=a_xt^2\\t=\sqrt{\frac{2x}{a}}\\t=\sqrt{\frac{2(3.2m)}{8.134\frac{m}{s^2}}}\\t=0.79 s$

8 0

4 years ago