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3 years ago

What are two reasons why density is a useful physical property for identifying substances?

1 answer:

4 0

Some substances look alike and the density can help you determine which is which. It also helps to tell which is heavier than the other.

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The man who discovered that even individual light particles have wave characteristics was:

wolverine [178]

I am almost positive that it was, ISSAC NEWTON

4 0

3 years ago

Read 2 more answers

A stalled car is being pushed up a hill at constant velocity by three people. the net force on the car is

frosja888 [35]

I think you need more information like the force of gravity and the force of the three people. Once you combine the two, however, you should get the net force.

6 0

2 years ago

The tub of a washer goes into its spin-dry cycle, starting from rest and reaching an angular speed of 2.0 rev/s in 10.0 s. At th

Arte-miy333 [17]

Answer:

22 revolutions

Explanation:

2 rev/s = 2*(2π rad/rev) = 12.57 rad/s

The angular acceleration when it starting

$\alpha_a = \frac{\Delta \omega}{\Delta t} = \frac{12.57}{10} = 1.257 rad/s^2$

The angular acceleration when it stopping:

$\alpha_o = \frac{\Delta \omega}{\Delta t} = \frac{-12.57}{12} = -1.05 rad/s^2$

The angular distance it covers when starting from rest:

$\omega^2 - 0^2 = 2\alpha_a\theta_a$

$\theta_a = \frac{\omega^2}{2\alpha_a} = \frac{12.57^2}{2*1.257} = 62.8 rad$

The angular distance it covers when coming to complete stop:

$0 - \omega^2 = 2\alpha_o\theta_o$

$\theta_o = \frac{-\omega^2}{2\alpha_o} = \frac{-12.57^2}{2*(-1.05)} = 75.4 rad$

So the total angular distance it covers within 22 s is 62.8 + 75.4 = 138.23 rad or 138.23 / (2π) = 22 revolutions

6 0

3 years ago

Altitude is the angle measured above ____. North Pole horizon equator zenith

juin [17]

Altitude is the angle measured above the horizon

5 0

3 years ago

Read 2 more answers

The battery for a certain cell phone is rated at 3.70 V. According to the manufacturer it can produce math]3.15 \times 10^{4} J[

AysviL [449]

Answer:

The average current that this cell phone draws when turned on is 0.451 A.

Explanation:

Given;

voltage of the phone, V = 3.7 V

electrical energy of the phone battery, E = 3.15 x 10⁴ J

duration of battery energy, t = 5.25 h

The power the cell phone draws when turned on, is the rate of energy consumption, and this is calculated as follows;

$P = \frac{E}{t}$

where;

P is power in watts

E is energy in Joules

t is time in seconds

$P = \frac{3.15*10^4}{5.25*3600s} = 1.667 \ W$

The average current that this cell phone draws when turned on:

P = IV

$I = \frac{P}{V} =\frac{1.667}{3.7} = 0.451 \ A$

Therefore, the average current that this cell phone draws when turned on is 0.451 A.

5 0

3 years ago