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3 years ago

WILL GIVE BRAINLIEST!

Physics

1 answer:

ella [17]3 years ago

5 0

A. momentum = mass x velocity
b. kinetic energy = 1/2 x mass x velocity^2
Although total momentum is conserved, total kinetic energy is not necessarily equal. It’s because Jay acted a force on the skateboard and increased the energy of the system.

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A coil of wire that is carrying a current and produces a magnetic field is.

Akimi4 [234]

A solenoid hope this is right

5 0

2 years ago

Your study buddy claims that an electron always experiences a force in an electric field, but not always in a magnetic field. do

timurjin [86]

It's true charged particles are always acted on by an electric field.when the velocity of the electron is parallel to the magnetic field, the magnetic force vanishes.

4 0

3 years ago

A student places an object with a mass of m on a disk at a position r from the center of the disk. The student starts rotating t

koban [17]

Answer:

The coefficient of static friction between the object and the disk is 0.087.

Explanation:

According to the statement, the object on the disk experiments a centrifugal force due to static friction. From 2nd Newton's Law, we can represent the object by the following formula:

$\Sigma F_{r} = \mu_{s}\cdot N = m\cdot \frac{v^{2}}{R}$ (1)

$\Sigma F_{y} = N - m\cdot g = 0$ (2)

Where:

$N$ - Normal force from the ground on the object, measured in newtons.

$m$ - Mass of the object, measured in newtons.

$g$ - Gravitational acceleration, measured in meters per square second.

$v$ - Linear speed of rotation of the disk, measured in meters per second.

$R$ - Distance of the object from the center of the disk, measured in meters.

By applying (2) on (1), we obtain the following formula:

$\mu_{s}\cdot m\cdot g = m\cdot \frac{v^{2}}{R}$

$\mu_{s} = \frac{v^{2}}{g\cdot R}$

If we know that $v = 0.8\,\frac{m}{s}$ , $g = 9.807\,\frac{m}{s^{2}}$ and $R = 0.75\,m$ , then the coefficient of static friction between the object and the disk is:

$\mu_{s} = \frac{\left(0.8\,\frac{m}{s} \right)^{2}}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (0.75\,m)}$

$\mu_{s} = 0.087$

The coefficient of static friction between the object and the disk is 0.087.

5 0

3 years ago

When an RL circuit is connected to a battery, which is true about its initial and final states?

zubka84 [21]

Answer:A

Explanation:

In R-L circuit current is given by

$i=i_0\left [ 1-e^{\frac{-t}{L/R}}\right ]$

where i=current at any time t

$i_0=maximum\ current$

R=resistance

L=Inductance

at t=0 $e^{\frac{-t}{L/R}}$ approaches to 1

therefore $i=i_0\left [ 1-1\right ]$

i=0

when t approaches to $\infty$ , $e^{\frac{-t}{L/R}}$ approaches to zero

thus $i=i_0$

thus we can say that initially circuit act as broken wire with zero current

and it increases exponentially with time and act as ordinary connecting wire

7 0

3 years ago

A grocery cart with a mass of 15 kg is pushed at constant speed along an aisle by a force fp = 12 n which acts at an angle of 17

Korolek [52]

Given:

Mass of cart: 15kg

Aisle length = 14m

Angle = 17° below the horizontal

Force fp = 12 N

So, the solution would be like this for this specific problem:

1) W(by applied force) = F(applied) x s x cosθ 
=>W(a) = 12 x 14 x cos17* = 160.66 J 

2) By F(net) = F(applied) - F(friction) 
=>As v = constant => a = 0 => F(net) = 0
=>F(applied) = F(friction)
=>W(friction) = -F(friction) x s
=>W(friction) = -F(applied) x s
=>W(f) = -12 x 14 x cos17* = -160.56 J 

3) 0, as the displacement is perpendicular to Force 

4) 0, as the displacement is perpendicular to Force

To add, the force that is applied to an object by a person or another object is called the applied force.

8 0

3 years ago