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2 years ago

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A ball of mass 200 g rolls along the ground at a speed of 5.2 m/s. Calculate the kinetic energy of the ball. Give your answer to

one decimal place.

1 answer:

ololo11 [35]2 years ago

3 0

Here is the answer, hope help some

You might be interested in

Plz help The momentum of a baseball changes dramatically when struck by a bat.Momentum of the ball is not conserved. The best ex

Luda [366]

Answer:

When the bat hits the ball, it exerts some force on the ball. Just think about a home run hitter hitting a stationary ball. How far do you think it will go? Will it go more than 400 ft.? Probably not. While the kinetic energy transferred from the bat to the ball accounts for some energy of the ball, it does not account for all. Where is the mysterious energy coming from?

The answer is conservation of momentum. I just said momentum is conserved but how do I know that? I know that because of Newton's 2nd law: F=ma (Force equals mass times acceleration)

Conservation of momentum means that the harder you throw you, the harder the ball will bounce back at you. That is the reason it is easier to hit a home run on a fast ball than a curveball.

Conservation of momentum also means that the bat can transfer some of its momentum to the ball. This is why it is better to use a heavier bat if you swing just as fast. The momentum is the product of the mass and velocity, so to make it easier to understand;

a heavier bat swung at the same speed as a lighter bat will have more momentum.

8 0

2 years ago

Sophia is planning on going down an 8-m water slide. Her weight is 50 N. She knows that she has gravitational potential energy (

Pepsi [2]

Answer:The higher up an object is the greater its gravitational potential energy. The larger the distance something falls through the greater the amount of GPE the object loses as it falls. As most of this GPE gets changed into kinetic energy, the higher up the object starts from the faster it will be falling when it hits the ground. So a change in gravitational potential energy depends on the height an object moves through.

Explanation: Lifting an apple up 1 metre is easier work than lifting an apple tree the same height. This is because a tree has more mass, so it needs to be given more gravitational potential energy to reach the same height.

6 0

2 years ago

A girl is shown at position A on a swing when the seat is directly below the support bar. The seat is then at height A as shown

MrRa [10]

Answer:

<u></u>

<u>1. The potential energy of the swing is the greatest at the position B.</u>

<u>2. As the swing moves from point B to point A, the kinetic energy is increasing.</u>

Explanation:

Even though the syntax of the text is not completely clear, likely because it accompanies a drawing that is not included, it results clear that the posittion A is where the seat is at the lowest position, and the position B is upper.

The gravitational <em>potential energy </em>is directly proportional to the height of the objects with respect to some reference altitude. Thus, when the seat is at the position A the swing has the smallest potential energy and when the seat is at the <em>position B the swing has the greatest potential energy.</em>

Regarding the forms of energy, as the swing moves from point B to point A, it is going downward, gaining kinetic energy (speed) at the expense of the potential energy (losing altitude). When the seat passes by the position A, the kinetic energy is maximum and the potential energy is miminum. Then the seat starts to gain altitude again, losing the kinetic energy and gaining potential energy, up to it gets to the other end,

7 0

2 years ago

Read 2 more answers

A negative charge of -0.550 μC exerts an upward 0.900-N force on an unknown charge that is located 0.300 m directly below the fi

allochka39001 [22]

Answer:

a. q2 = 16.4μC, positive charge

b. F = 0.900N

c. downward

Explanation:

a. In order to calculate the charge of the unknown charge you use the following formula, for the electric force between two charges:

$F_e=k\frac{q_1q_2}{r^2}$ (1)

k: Coulomb's constant = 8.98*10^9Nm^2/C^2

r: distance between the charges = 0.300m

q1: charge 1 = -0.550 μC = 0.550*10^-6C

q2: charge 2 = ?

Fe: electric force = 0.900N

The force exerted in the second charge points upward, then, the sign of the second charge is positive because this charge is getting closer to the first one.

You solve the equation (1) for the second charge ans replace the values of the other parameters:

$q_2=\frac{r^2F_e}{kq_1}=\frac{(0.300m)^2(0.900N)}{(8.98*10^9Nm^2/C^2)(0.550*10^{-6}C)}\\\\q_2=1.64*10^{-5}C\\\\q_2=16.4*10^{-6}C=16.4*10\mu C$

The values of the second charge is 1.64 μC

b. By the third Newton Law, you have that the force exerted in the second charge is equal to the force exerted by the first charge on the second one.

The force exerted on the first charge is 0.900N

c. The charges are attracting between them, then, the force exerted on the first charge is pointing downward.

3 0

2 years ago

La luz pasa del medio A al medio B formando un ángulo de 35° con la frontera horizontal entre ambos. Si el ángulo de refracción

zaharov [31]

Answer:

Índice de refracción entre los dos medios = 1,43

Refractive index between the two media = 1.43

Explanation:

El índice de refracción entre dos medios se explica mejor entendiendo primero la refracción.

Cuando las olas se mueven de un medio a otro, a menudo experimentan un cambio de dirección con respecto al medio en el que viajan.

Por lo tanto, el índice de refracción se expresa como el seno del ángulo de incidencia dividido por el seno del ángulo de refracción.

El seno del ángulo de incidencia y la refracción utilizados en esta fórmula de índice de refracción se miden respectivamente con respecto a la vertical.

En esta pregunta Ángulo de incidencia = 35° a la horizontal = (90° - 35°) a la vertical = 55° a la vertical.

Ángulo de refracción = 35°

Índice de refracción entre los dos medios

= (Sin 55°) ÷ (Sin 35°)

= 0.8192 ÷ 0.5736

= 1.428 = 1.43 a 2 d.p.

¡¡¡Espero que esto ayude!!!

English Translation

The light passes from medium A to medium B at an angle of 35 ° with the horizontal border between the two. If the angle of refraction is also 35 °, what is the relative refractive index between the two media?

Solution

The refractive index between two media is best explained by first understanding refraction.

When waves move from one medium to another, they often experience a change in direction with respect to the medium in which they are travelling.

Hence, refractive index is expressed as the sine of angle of incidence dibided by the sine of angle of refraction.

The sine of angle of incidence and refraction used in this refractive index formula are both respectively measured with respect to the vertical.

In this question,

Angle of incidence = 35° to the horizontal = (90° - 35°) to the vertical = 55° to the vertical.

Angle of refraction = 35°

Refractive index between the two media

= (Sin 55°) ÷ (Sin 35°)

= 0.8192 ÷ 0.5736

= 1.428 = 1.43 to 2 d.p.

Hope this Helps!!!

3 0

2 years ago