The color that an object appears to be depends on the select one:

When people use plastic combs on their hair, the combs become negatively charged. Which statements about this situation are true

Vadim26 [7]

The answer would be:
The comb gains electrons.
The hair loses electrons.

In chemistry, the charge depends on the electrons and protons. The electron will give negative charge and proton will give the positive charge. Proton is located in the nucleus of the atoms so it won't easily move like electron which located in the orbit in the atoms perimeter. So, ignore the option with the proton.
If the combs become negatively charged, that means it gain some electron. Since something gain electron, that means another thing is losing an electron. That electron comes from the hair.

3 0

4 years ago

Read 2 more answers

Suppose you observed the equation for a traveling wave to be y(x, t) = A cos(kx − ????t), where its amplitude of oscillations wa

OLga [1]

Answer:

Explanation:

The equation for a traveling wave as expressed as y(x, t) = A cos(kx − $\omega$ t) where An is the amplitude f oscillation, $\omega$ is the angular velocity and x is the horizontal displacement and y is the vertical displacement.

From the formula; $k =\frac{2\pi x}{\lambda} \ and \ \omega = 2 \pi f$ where;

$\lambda \ is\ the \ wavelength \ and\ f \ is\ the\ frequency$

Before we can get the transverse speed, we need to get the frequency and the wavelength.

frequency = 1/period

Given period = 2/15 s

Frequency = $\frac{1}{(2/15)}$

frequency = 1 * 15/2

frequency f = 15/2 Hertz

Given wavelength $\lambda$ = 2m

Transverse speed $v = f \lambda$

$v = 15/2 * 2\\\\v = 30/2\\\\v = 15m/s$

Hence, the transverse speed at that point is 15m/s

8 0

3 years ago

Suppose you have a cylinder filled with diatomic oxygen (O2) and it is running low. The cylinder is shown above, is made of stee

Rudiy27

Answer:

The number of O₂ molecules that are left in the cylinder is 1.70x10²⁴.

Explanation:

The number of oxygen molecules can be found using the Ideal Gas law:

$PV = nRT$

Where:

P: is the pressure = 100 psi

V: is the volume = 10 L

n: is the number of moles =?

T: is the temperature = 20 °C = 293 K

R: is the gas constant = 0.082 L*atm/(K*mol)

Hence, the number of moles is:

$n = \frac{PV}{RT} = \frac{100 psi*\frac{1 atm}{14.7 psi}*10 L}{0.082 L*atm/(K*mol)*293 K} = 2.83 moles$

Now, the number of molecules can be found with Avogadro's number:

$n_{m} = \frac{6.022 \cdot 10^{23}\: molecules}{1\: mol}*2.83 moles = 1.70 \cdot 10^{24} \: molecules$

Therefore, the number of O₂ molecules that are left in the cylinder is 1.70x10²⁴.

I hope it helps you!

3 0

3 years ago

A 2.7 kg ball is thrown upward with an initial speed of 20.0 m/s from the edge of a 45.0-m-high cliff. At the instant the ball i

madam [21]

Answer:

(a) At what angle above the horizontal should the ball be thrown so that the runner will catch it just before it hits the ground? (b) How far does the woman run before she catches the ball?

(a) = 72.54°

≅ 72.5°

(b) = 33.4 m

Explanation:

see the attached file below

4 0

3 years ago

A 26 kg child is coasting at 2.0 m/s over flat ground in a 5.0 kg wagon. The child drops a 1.5 kg ball from the side of the wago

RoseWind [281]

Answer:

Final speed = 2.067 m/s

Explanation:

We are told that the child weighs 26 kg.

Also, that the wagon weighs 5kg.

Thus,initial mass of the child and wagon with ball is;

m_i = 26 + 5 = 31 kg.

Also, we are told that the child now dropped 1.5 kg ball from the wagon. So,

Final mass is;

m_f = 26 + 5 - 1 = 30 kg

Now, from conservation of linear momentum, we know that;

Initial momentum = final momentum

Thus;

m_i * v_i = m_f * v_f

Where v_i is initial velocity and v_f is final velocity.

Making v_f the subject, we have;

v_f = (m_i * v_i)/m_f

We are given that initial velocity v_i = 2 m/s

Plugging in the relevant values, we have;

v_f = (31 * 2)/30

v_f = 2.067 m/s

7 0

3 years ago