Help me with physics

A negative charge is moved from point A to point B along an equipotential surface. Which of the following statements must be tru

elena-s [515]

Answer:

C) No work is required to move the negative charge from point A to point B.

Explanation:

An equipotential surface is defined as a surface connecting all the points at the same potential.

Therefore, when a charge moves along an equipotential surface, it moves between points at same potential.

The work done when moving a charge is given by

$W=q\Delta V$

where

q is the charge

$\Delta V$ is the potential difference between the initial and final point of motion of the charge

However, the charge in this problem moves along an equipotential surface: this means that the potential does not change, so

$\Delta V=0$

And so, the work done is also zero.

7 0

4 years ago

Acceleration is positive when you are speeding up.

Vikki [24]

Answer:

B Negative

Explanation:

Its negative because when your going 25 mph your moving faster and when your coming up to the stop sign you will start to slow down going 10 mph then 0 mph when you reach the stop sign so it will be negative.

8 0

2 years ago

When you are on a roller coaster, you are constantly transforming from Potential to Kinetic energy and back. Explain how these e

andreev551 [17]

Answer:

The two types of energy possessed by the roller coaster are:

- Potential energy: it is the energy possessed by the roller coaster due to its position. It is calculated as

$PE=mgh$

where

m is the mass of the roller coaster

g is the acceleration due to gravity

h is the height of the roller coaster relative to the ground

- KInetic energy: it is the energy possessed by the roller coaster due to its motion. It is calculated as

$KE=\frac{1}{2}mv^2$

where

v is the speed of the roller coaster

Moreover, according to the law of conservation of energy, the total mechanical energy of the roller coaster (the sum of potential+kinetic energy) is constant during the motion:

$E=PE+KE=const.$

This implies that:

- When PE increases (because h increases), KE decreases (because v decreases)

- When PE decreases (because h decreases), KE increases (because v increases)

Now we can apply these conclusions to the motion of the roller coaster:

- When it moves from A to B, potential energy is converted into kinetic energy, so PE decreases and KE increases

- When it moves from B to C, kinetic energy is converted into potential energy, so PE increases and KE decreases

- When it moves from C to D, potential energy is converted into kinetic energy, so PE decreases and KE increases

- When it moves from D to E, kinetic energy is converted into potential energy, so PE increases and KE decreases

8 0

3 years ago

You throw a basketball and a tennis ball across the classroom so that each ball has the exact same momentum. Explain how this is

Helga [31]

Answer:

It is possible by increasing the speed of the tennis ball by a factor of (Mass of the tennis ball)/(Mass of the basketball)

Explanation:

The momentum of a body = The bod's mass × The body's velocity

Therefore, the momentum of a given mass of an object, such as a tennis ball can be increased by increasing the velocity or speed of the object. Whereby the speed of the ball, v₁, is increased such that the momentum of the basketball and the tennis ball will be the same, is given by the following equation

Mass of the basketball × v₂ = Mass of the tennis ball × v₁

Therefore, v₁/v₂ = (Mass of the tennis ball)/(Mass of the basketball)

7 0

3 years ago

A box is sliding down an incline tilted at a 11.1° angle above horizontal. The box is initially sliding down the incline at a sp

raketka [301]

Answer:s=0.68 m

Explanation:

Given

Inclination $\theta =11.1^{\circ}$