The motion of an object looks different to observers in different

Charge is distributed uniformly on the surface of a large flat plate. the electric field 2 cm from the plate is 30 n/c. the elec

AysviL [449]

The electric field produced by a large flat plate with uniform charge density on its surface can be found by using Gauss law, and it is equal to
$E= \frac{\sigma}{2\epsilon_0}$
where
$\sigma$ is the charge density
$\epsilon_0$ is the vacuum permittivity

We see that the intensity of the electric field does not depend on the distance from the plate. Therefore, the strenght of the electric field at 4 cm from the plate is equal to the strength of the electric field at 2 cm from the plate:
$E=30 N/C$

7 0

1 year ago

For a short time the position of a roller-coaster car along its path is defined by the equations r=25 m, θ=(0.3t) rad, and z=(−8

Mariana [72]

Answer:

Velocity = v = 2.24m/s

Acceleration = a = 0.20m/s²

Explanation:

Please see attachment below.

Given

z=(−8 cosθ) and θ = 0.3t

z = -8Cos (0.3t)

V = dz/dt

a = v²/R.

Please see full solution below.

8 0

1 year ago

A system absorbs 52 joules of heat and does work using 25 joules of energy. What is the change in the internal energy of the sys

motikmotik

The change in internal energy is $\Delta U=Q+W$ . Where $\Delta U$ is change in internal energy. $Q$ is heat added to the system (absorbed by the system). $W$ work done on the system. $W$ is taken as positive if work is done on the system and negative if work is done by the system. Here $Q=52$ and $W=-25$ , hence change in internal energy is

$\Delta U=52-25\\ \Delta U=27$

Change in internal energy of the system is 27 J. Internal energy increases.

8 0

2 years ago

Read 2 more answers

"I know how many electrons the atom has, and I know how many protons it has, but I don't know whether or not it is neutral," a f

finlep [7]

The atom is neutral (no electric charge)

Explanation:

An atom consists of:

- A nucleus, containing protons (positively charged) and neutrons (no electric charge)

- Electrons (negatively charged), orbiting around the nucleus

The charge of one proton is equal in magnitude (but opposite in sign) to that of an electron, and it is

$e=1.6\cdot 10^{-19} C$

Moreover, for a normal atom, the number of protons in the nucleus is equal to the number of electrons around it.

This means that for a normal atom, the net charge of it is zero, since the total charge of the protons balance that of the electrons.

So, the answer to the question is that the atom is neutral.

Learn more about atoms here:

brainly.com/question/2757829

#LearnwithBrainly

4 0

1 year ago

A spring (k = 802 N/m) is hanging from the ceiling of an elevator, and a 5.0-kg object is attached to the lower end. By how much

love history [14]

Answer:

0.00256 m

Explanation:

For this case, we should use the Hook Law for a spring:

F= -Kx , the negative sign indicates that the force that tries to “restore” the original status of the spring, and is against the force that causes the spring´s displacement

This is, the force F required to stretch an elastic object (for example, a metal spring), is directly proportional the extension “x” of the spring

“x” can be the extension or compression of the spring, and “K” is a constant (in units of N/m)

We also know that, according to Newton´s Law:

F=m*a

m= mass

a= acceleration

Then:

m*a= -Kx

Finally, the spring has an original length of L₀, so:

- If the spring is compressed, the final strength will be: L = L₀ – x

- If the spring is extended, the final strength will be: L = L₀ + x

According to the statement:

K = 802 N/m

a = 0.41 m/s2

m = 5 Kg

Then:

x =- (m*a)/K = (5x0.41)/802 = 0.00256 m (we do not consider the negative sign, due to above explanation: it only indicates that the restoration force is always against the force imposed on the spring )

So, if the spring has an original length of L₀, when the elevator is accelerating upwards, the spring will stretch from L₀ to (L₀ – 0.00256) m

6 0

1 year ago