All categories

3 years ago

Please help ASAP. There are 3 question it would be a big help if you can answer any.

Physics

2 answers:

sesenic [268]3 years ago

7 0

Answer:

number 1 is falling freely number 2 I think the 2nd option number 3 3rd option

erastova [34]3 years ago

7 0

1). If you're standing on a scale in an elevator, and the scale reads much less than your real weight, then the elevator must be accelerating downward.

(Think of the extreme limit: If the elevator is in free-fall, accelerating down at 9.8 m/s², then you'll apear to be weightless ... the scale will read zero.)

2). A 100 kg man is standing in an elevator, accelerating up at 2.0 m/s².

The net force acting on him is F = m·a = (100 kg) x (2.0 m/s²) = 200 N up.

The forces acting on him are:

-- gravity, m·g = (100 kg) x (9.8 m/s²) = 980 N down

-- elevator floor force . . . EF up

Net force = (980N down) + (EF up)

(200N up) = (980N down) + (EF up)

Add (980N up) to each side:

(200N up + 980N up) = EF up

Elevator force = 1180N up.

Pick the second choice: 1.2 x 10³ N up

3). My computer is resting on my desk.

There are many forces acting on my computer, and they are all balanced.

That means the NET force acting on my computer is zero.

If the net force were NOT zero, then my computer would be accelerating in the direction of the net force. But it's at rest. So the net force must be zero.

You might be interested in

Visible light passes through a diffraction grating that has 900 slits per centimeter, and the interference pattern is observed o

kobusy [5.1K]

Answer:

$\Delta \lambda=14.3\ nm$

Explanation:

It is given that,

The number of lines per unit length, N = 900 slits per cm

Distance between the formed pattern and the grating, l = 2.3 m

n the first-order spectrum, maxima for two different wavelengths are separated on the screen by 2.98 mm, $\Delta Y=2.98\ mm = 0.00298\ m$

Let d is the slit width of the grating,

$d=\dfrac{1}{N}$

$d=\dfrac{1}{900\ cm}$

$d=1.11\times 10^{-5}\ m$

For the first wavelength, the position of maxima is given by :

$y_1=\dfrac{L\lambda_1}{d}$

For the other wavelength, the position of maxima is given by :

$y_2=\dfrac{L\lambda_2}{d}$

So,

$\Delta \lambda=\dfrac{\Delta y d}{l}$

$\Delta \lambda=\dfrac{0.00298\times 1.11\times 10^{-5}}{2.3}$

$\Delta \lambda=1.43\times 10^{-8}\ m$

$\Delta \lambda=14.3\ nm$

So, the difference between these wavelengths is 14.3 nm. Hence, this is the required solution.

3 0

3 years ago

How do magnetic forces repel or attract?

Lerok [7]

“Magnets are surrounded by an invisible magnetic field that is made by the movement of electrons, the subatomic particles that circle the nucleus of an atom”

“Every magnet has both a north and a south pole. When you place the north pole of one magnet near the south pole of another magnet, they are attracted to one another. When you place like poles of two magnets near each other (north to north or south to south), they will repel each other.”

3 0

3 years ago

How can you tell animal and plant cells apart

Lynna [10]

Well there are a couple ways. 1: The easiest, plant cells have a cell wall or extra protection. You will not find this on an animal cell, as there is only a membrane. 2: Chloroplast. This also will not be found in animal cells as they produce the plant's green color as well as the sugar. Hope this helps!

8 0

3 years ago

In a particular experiment to study the photoelectric effect, the frequency of the incident light and the temperature of the met

qwelly [4]

Answer:

B. The number of electrons emitted from the metal per second increases.

Explanation:

Light consists of photons . Energy of each photon depends upon frequency of light . The increase in intensity increases the number of photons . It does not increase energy of photons .

So if a high intensity light falls on a photosensitive plate , each photon ejects one electron . So number of electrons increases if we increase intensity of photon. It does not increase kinetic energy of ejected electrons . Work function depends upon the nature of plate.

6 0

3 years ago

Which describes a function of the thalamus?

Natalka [10]

Answer:

figure it out bot

Explanation:

jhkhllkhlkh

4 0

3 years ago

Read 2 more answers