All categories

3 years ago

A car initally at rest accelerates in a straight line at 3 m/s2 what will be its speed after 2 seconds

Physics

1 answer:

Ainat [17]3 years ago

5 0

Answer

In this Question we have given

acceleration, a=3m/s^2

and time, t=2s

we have to find speed, v=?

Apply newton's Ist equation of motion which goes as

$[tex]v =u + at\\ Here v is final velocity\\u - initial velocity\\a-acceleration\\t- time$ [/tex]

In this problem the car starts from rest it means initial velocity, u =0.

Putting values of u, a and t in first equation of motion

$v=0+3*2\\v=6m/s$

Therefore speed of car after 2 second will be 6m/s

Note: In this type of problems. First check the units of all quatities. As all the quantities must be first changed into matching units i.e cgs or s.i. units before applying the equation.

You might be interested in

Which of the following are true (choose all that apply)? Sound can travel through a vacuum. -Sound can travel through water. Lig

Lunna [17]

Answer:

option (A) - false

option (B) - true

option (C) - true

option (D) - true

option (E) - true

option (F) - true

Explanation:

The sound waves are mechanical waves that means they need a medium to travel.

The light waves are non mechanical waves it means they do not need a medium to travel.

Sound cannot travel trough vacuum.

Sound can travel through air and water.

Light can travel trough vacuum and in air and in water.

7 0

3 years ago

A large raindrop-the type that lands with a definite splat-has a mass of 0.0014 g and hits your roof at a speed of 8.1 m/s. a. W

DENIUS [597]

Answer

given,

mass of the drop, m = 0.0014 g

speed of the drop, u = 8.1 m/s

a) Change in momentum is equal to impulse

final velocity of the drop, v = 0 m/s

J = m ( v - u )

J = 0.0014 x 10⁻³ x ( 0 - 8.1 )

J = -1.134 x 10⁻⁵ kg.m/s

impulse of the roof = - J = 1.134 x 10⁻⁵ kg.m/s

b) time, t = 0.37 m s

impact of force = ?

we know

J = F x t

1.134 x 10⁻⁵ = F x 0.37 x 10⁻³

F = 0.031 N

the magnitude of the force of the impact is equal to F = 0.031 N

5 0

3 years ago

Loghan and Kyle want to see if the type of ice cream in the freezer affects how hard or soft it is. Each time they placed a new

poizon [28]

True.....................

7 0

3 years ago

Why is solar energy transferred to earth by radiation

kodGreya [7K]

Answer: Because between the Earth and Sun there is vacuum

There are three ways in which heat is transmitted:

1. By Conduction, when the transmission is by the direct contact.

2. By Convection, heat transfer in fluids (like water or the air, for example).

3. By Radiation, by the electromagnetic waves (they can travel through any medium and in vacumm) .

So, the space between the Earth and the Sun is vacuum, this means the energy cannot be transmitted by convection, nor conduction. It must be transmitted by electromagnetic waves that are able to travel with or without a medium, and this is called radiation.

4 0

3 years ago

A .005kg projectile leaves a 1500kg launcher with a velocity of 750 m/s. What is the recoil velocity of the projectile

docker41 [41]

Answer:

The recoil velocity of the projectile is 0.0025m/s

Explanation:

Given:

Mass of the projectile =0.005kg

Mass of the launcher = 1500kg

Velocity = 750 m/s.

To Find:

The recoil velocity of the projectile = ?

Solution:

The recoil velocity is the obtained by dividing the "recoil momentum" by the "mass of the recoil body". The recoil momentum is equal to the momentum of the other body. The momentum of the other body is equal to it mass times its velocity.

Lets find the recoil momentum,

Recoil momentum = mass of the projectile X velocity

Recoil momentum = $0.005 \times 750$

Recoil momentum = 3.75

Now Recoil Velocity,

Recoil Velocity = $\frac{\text { Recoil Momentum}}{\text {Mass of the launcher}}$

Recoil Velocity = $\frac{ 3.75}{1500}$

Recoil Velocity = 0.0025m/s

7 0

3 years ago