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2 years ago

I need help on a english book report

Physics

1 answer:

lianna [129]2 years ago

7 0

Answer:

I can help, but

Explanation:

Where is the question?

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Match the term to the correct description.

Sedaia [141]

1. Proton
2. negative ion
3. electric charge
4. electron
5. repel
6. attract
7. positive ion

7 0

3 years ago

Read 2 more answers

4. The Earth is the only planet that contains storms. Tor F 5. Lightning is a form of energy made up of protons that move from c

Mumz [18]

Answer:

4. F

5. F

Explanation:

jupiter constantly has hurricanes and uranus has storms often too.

lightning can move many ways including from cloud to cloud and even from ground ton sky (seriously look it up it's cool)

6 0

3 years ago

A 1.50x103-kilogram car is traveling east at 30 meters per second.

frez [133]

Answer:

$39000\ \text{kg m/s}$

West

Explanation:

m = Mass of car = $1.3\times 10^{3}\ \text{kg}$

t = Time = 9 seconds

u = Initial velocity = 30 m/s

v = Final velocity = 0

Impulse is given by

$J=m(v-u)\\\Rightarrow J=1.3\times 10^3(0-30)\\\Rightarrow J=-39000\ \text{kg m/s}$

The magnitude of the total impulse applied to the car to bring it to rest is $39000\ \text{kg m/s}$ .

The direction is towards west as the sign is negative.

7 0

2 years ago

2. a) A disc rotates about its axis at speed 25 revolutions per minute and takes 15 s to stop. Calculate the

ASHA 777 [7]

The statement shows a case of rotational motion, in which the disc <em>decelerates</em> at <em>constant</em> rate.

i) The angular acceleration of the disc ( $\alpha$ ), in revolutions per square second, is found by the following kinematic formula:

$\alpha = \frac{\omega_{f}-\omega_{o}}{t}$ (1)

Where:

$\omega_{o}$ - Initial angular speed, in revolutions per second.
$\omega_{f}$ - Final angular speed, in revolutions per second.
$t$ - Time, in seconds.

If we know that $\omega_{o} = \frac{5}{12}\,\frac{rev}{s}$ , $\omega_{f} = 0\,\frac{rev}{s}$ y $t = 15\,s$ , then the angular acceleration of the disc is:

$\alpha = \frac{0\,\frac{rev}{s}-\frac{5}{12}\,\frac{rev}{s}}{15\,s}$

$\alpha = -\frac{1}{36}\,\frac{rev}{s^{2}}$

The angular acceleration of the disc is $\frac{1}{36}$ radians per square second.

ii) The number of rotations that the disk makes before it stops ( $\Delta \theta$ ), in revolutions, is determined by the following formula:

$\Delta \theta = \frac{\omega_{f}^{2}-\omega_{o}^{2}}{2\cdot \alpha}$ (2)

If we know that $\omega_{o} = \frac{5}{12}\,\frac{rev}{s}$ , $\omega_{f} = 0\,\frac{rev}{s}$ y $\alpha = -\frac{1}{36}\,\frac{rev}{s^{2}}$ , then the number of rotations done by the disc is:

$\Delta \theta = 3.125\,rev$