A bus travels a distance of 100 km in 2.5 h. Calculate its average speed.

What is the centripetal force that holds planets in orbit?

Fudgin [204]

<h2>Answer: Gravity force</h2>

If we approximate the orbit of the planets around the Sun to circular orbits with a uniform circular motion, where the velocity $\vec{V}$ is a vector, whose direction is perpendicular to the radius $r$ of the trajectory; the acceleration $\vec{a}$ is directed towards the center of the circumference (that's why it's called centripetal acceleration).

Now, according to Newton's 2nd law, the force $\vec{F}$ is directly proportional and in the same direction as the acceleration:

$\vec{F}=m.\vec{a}$

Therefore the net force resulting from the movement of a planet orbiting the Sun points towards the center of the circle, this is called Centripetal Force which is a central force that in this case is equal to the gravity force.

8 0

3 years ago

A 5 kg object moving to the right at 4 m/s collides inelastically with a 5 kg object

skad [1K]

Answer:

The linear momentum of a particle with mass m moving with velocity v is defined as

p = mv (7.1)

Linear momentum is a vector . When giving the linear momentum of a particle you must

specify its magnitude and direction. We can see from the definition that its units must be

kg·m

s

. Oddly enough, this combination of SI units does not have a commonly–used named so

we leave it as kg·m

s

!

The momentum of a particle is related to the net force on that particle in a simple way;

since the mass of a particle remains constant, if we take the time derivative of a particle’s

momentum we find

dp

dt = m

dv

dt = ma = Fnet

so that

Fnet =

dp

dt (7.2)

5 0

2 years ago

A force that results from charged particles is called?

olchik [2.2K]

A force that results from charged particles is called<u> </u><u>"electrostatic force".</u>

Hope this helps!

-Thanks!

-Charlie

7 0

3 years ago

Read 2 more answers

A 2.0 kg book is lying on a 0.78 m -high table. You pick it up and place it on a bookshelf 2.1 m above the floor.Part ADuring th

zloy xaker [14]

Given data:

* The mass of the book is 2 kg.

* The initial height of the book is 0.78 m.

* The final height of the book is 2.1 m.

Solution:

(A). The work done by the gravity on the book is,

$W=mg(h_f-h_i)$

where m is the mass, g is the acceleration due to gravity, h_i is the initial height and h_f is the final height,

The work is done in moving the object in upward direction where as the gravitational force is acting in the down ward direction. Thus, the value g (acceleration due to gravity) is taken as negative in this case.

Substituting the known values,

$\begin{gathered} W=2\times(-9.8)\times(2.1-0.78) \\ W=-19.6\times1.32 \\ W=-25.9\text{ J} \end{gathered}$

Thus, the work done by the gravitational force is -25.9 J.

(B). The work done by the hand on the moving the book is,

$\begin{gathered} W_1=-W \\ =25.9\text{ J} \end{gathered}$

Thus, the work done by the hand on the book is 25.9 J.

7 0

1 year ago

Which word means "to get away from something"? <br> a become b dream c escape d practice

klemol [59]

The correct answer is - c. escape.

The word ''escape'' means to get away from something. This word can be used for multiple different situations, and it can refer to both physical and psychological matters.

In a physical sense it can be used to escape from certain unpleasant, or dangerous situation. Example: I have to escape from this prison.

In a psychological sense it can be used to escape, move away, from a certain state of mind. Example: I have to find an escape from my depressive thoughts.

5 0

3 years ago