All categories

3 years ago

Please! Help..! It is really hard for me right know

Physics

1 answer:

Levart [38]3 years ago

6 0

$\frac{75}{10} = 7.5$

You might be interested in

The rest deltoid row is a back exercise true or false

bixtya [17]

False because your deltoids are in your shoulders not your back

3 0

3 years ago

Based on molecular orbital theory, the only molecule in the list below that has unpaired electrons is ________.

xenn [34]

The answer is Radicals.

6 0

2 years ago

A. An automobile mass is 3.5 x103 kg. If the forward thrust (Fnet)

katrin [286]

Answer:

a = 0.8 m/s^2

Explanation:

Force equation: F = ma

F = ma -> a = F/m = 2.8*10^3 N / 3.5*10^3 kg = 0.8 m/s^2

8 0

3 years ago

Plain electromagnetic wave (in air) has a frequency of 1 MHz and its B-field amplitude is 9 nT a. What is the wavelength in air?

Norma-Jean [14]

Answer:

Part a)

$\lambda = 300 m$

Part b)

$E = 2.7 N/C$

Part c)

$I = 9.68 \times 10^{-3} W/m^2$

$P = 3.22 \times 10^{-11} N/m^2$

Explanation:

Part a)

As we know that frequency = 1 MHz

speed of electromagnetic wave is same as speed of light

So the wavelength is given as

$\lambda = \frac{c}{f}$

$\lambda = \frac{3\times 10^8}{1\times 10^6}$

$\lambda = 300 m$

Part b)

As we know the relation between electric field and magnetic field

$E = Bc$

$E = (9 \times 10^{-9})(3\times 10^8)$

$E = 2.7 N/C$

Part c)

Intensity of wave is given as

$I = \frac{1}{2}\epsilon_0E^2c$

$I = \frac{1}{2}(8.85 \times 10^{-12})(2.7)^2(3\times 10^8)$

$I = 9.68 \times 10^{-3} W/m^2$

Pressure is defined as ratio of intensity and speed

$P = \frac{I}{c} = \frac{9.68\times 10^{-3}}{3\times 10^8}$

$P = 3.22 \times 10^{-11} N/m^2$

6 0

3 years ago

| A 1.0 kg stone is dropped from a bridge 100 m above a canyon. What will be the kinetic energy of the stone after it

Mnenie [13.5K]

Answer:

Option D

490 J

Explanation:

When at a height of 100 am above and released, the ball initially posses only potential energy. When it falls, some potential energy is converted to kinetic energy.

Initial potential energy= mgh where m is the mass, g is the acceleration due to gravity and h is height. Substituting 1 Kg for m, 9.81 for g and 100 m for h then

PE initial = 1*9.81*100= 981 J

At 50 m, PE will be 1*9.81*50=490.5 J

Subtracting PE at 50 m from initial PE we get the energy that has been converted to kinetic energy hence

981-490.5= 490.5 J

Approximately, 490 J

8 0

3 years ago