Ask question

Ask question

All categories

Anestetic [448]

3 years ago

5

A red rubber ball rolls down a hill from rest with an acceleration of 7.8 m/s 2 . How fast is it moving after it has traveled 5

m?

1 answer:

masya89 [10]3 years ago

7 0

Answer:

39 m/s

Explanation:

You might be interested in

Analyze that, “Convection is equal to the Conduction plus fluid flow.”

igomit [66]

Answer:

Convection is equal to the conduction plus fluid flow.

Explanation:

Convection is a mode of heat transfer that requires the movement of the molecules of the medium from one point to another. It takes place majorly in fluids (liquids and gases). While conduction is a process by which heat is transfered by the vibtation of molecules of a medium at their possitions, thereby colliding with other neighbouring molecules to transmit heat.

Before convection could occur, there must be conduction of heat by the molecules of the medium which causes their motion. According to the kinetic molecular theory, any molecule of the medium close to the source of heat conducts heat, becomes less dense and thus moves so that its initial position would be occupied by another denser molecule. This continous process generate convection or convectional current. Therefore, convection is as a result of conduction and fluid flow because a molecule must first conduct heat before it moves.

7 0

3 years ago

A street light is mounted at the top of a 15-ft-tall pole. a man 6 ft tall walks away from the pole with a speed of 4 ft/s along

Arlecino [84]

Answer: 2.67 ft/s

Explanation:

1) The diagram with the triangle that represents the situation is in the image attached.

2) Similarity properties

(x + y) / 15 = y/6

⇒ 6(x+y) = 15y

⇒ 6x + 6y = 15y

⇒ 6x = 15y - 6y

⇒ 6x = 9y

⇒ y = 6x / 9

⇒ y = 2x / 3

3) Velocity is the derivative respecto to time. Then, find the derivative respect to time, t, on both sides

dy/dt = (2/3)dx/dt

4) The statement tells v = dx/dt = 4 ft/s

⇒ dy/dt = (2/3) 4 ft/s = (8/3)m/s ≈ 2.67 ft/s

Notice that this speed is constant, it does not depends upon the distance of 30 ft.

5 0

3 years ago

Develop an equation (with a proportionality constant) that describes the relationship between the gravitational force (fgrav), t

ivolga24 [154]

According to newton's law of gravitation, the gravitational force(F) is directly proportional to the product mass of the moon(Mm) and the mass of the planet (Mp) and it is inversely proportional to the square of the separation between them.

Fg ∝ (Mp)(Mm) →(1)

Fg ∝ 1/d²→(2)

Combining equation (1) and (2),

Fg ∝ (Mp)(Mm)/d²

Fg = G(Mp)(Mm)/d²

This is an equation that describes the relation between mass of moon (Mm) and mass of planet (Mp) and separation(d) between them.

To support the claim in favuor of this equation we use this equation to obtain the value of acceleration due to gravity on earth.

Let m be the mass of an object on earth then Fg between earth (Mp) and mass of an object is obtained by:

Fg = G(Mp)(m)/R², where R= Radius of earth

This force is equal to the weight of an object i.e.,

g= G(Mp)/R²

Putting the values of G, Mp and R , we get, g=9.81 m/s²

which is the value we obtained on earth for acceleration due to gravity.

To know more about gravitational constant, visit:

brainly.com/question/13959861

#SPJ4

5 0

1 year ago

Describe the relationship between a moving object's mass and its kinetic energy.

Paladinen [302]

Answer:

$E=\dfrac{1}{2}mv^2$

Explanation:

If m is the mass of the object and v is the velocity of the object. The kinetic energy is due to the motion of an object. It is given by the relation as follows :

$E=\dfrac{1}{2}mv^2$

The above formula is used to find the kinetic energy of an object.

5 0

4 years ago

Think of a skateboarder riding down a hill. Once the skateboarder reaches the bottom of the hill, if she does not manually add m

anyanavicka [17]

The skateboard will stop because of friction.

6 0

3 years ago