Ask question

Ask question

All categories

3 years ago

10

A racing car is travelling at 70 m/s and accelerates at -14 m/s2. What would the car’s speed be after 3 s?

1 answer:

Leno4ka [110]3 years ago

3 0

<h3><u>Question</u><u>:</u></h3>

A racing car is travelling at 70 m/s and accelerates at -14 m/s^2. What would the car’s speed be after 3 s?

<h3><u>Statement:</u></h3>

A racing car is travelling at 70 m/s and accelerates at -14 m/s^2.

<h3><u>Solution</u><u>:</u></h3>

Initial velocity (u) = 70 m/s
Acceleration (a) = -14 m/s^2
Time (t) = 3 s
Let the velocity of the car after 3 s be v m/s
By using the formula,

v = u + at, we have

$v = 70 + ( - 14)(3) \\ = > v = 70 - 42 \\ = > v = 28$

So, the velocity of the car after 3 s is 28 m/s.

<h3><u>Answer:</u></h3>

The car's speed after 3 s is 28 m/s.

Hope it helps

You might be interested in

**HELP ASAP PLEASE!**

Setler79 [48]

They use a spectrograph so the answer would be B.

7 0

3 years ago

Read 2 more answers

What is the value of x?<br><br> 6x−2(x 4)=12

Ymorist [56]

Answer: The value of x is -6.

Explanation:

To calculate the value of 'x', we need to solve each function happening inthe equation.

The equation provided to us is $6x-2(4x)=12$

To solve this, we will multiply 4x with 2 and then subtract the like terms and finally, we evaluate the value of 'x'.

$6x-8x=12\\\\-2x=12\\\\x=\frac{12}{-2}\\\\x=-6$

Hence, the value of x will be -6.

5 0

3 years ago

Read 2 more answers

Which statement best describes the magnetic effect of a bar magnet

DIA [1.3K]

Answer;

B. The field is most concentrated at the poles of the magnet

Explanation;

A bar magnet is a rectangular object that has a magnetic field. It is usually made of iron or steel, but it can also be made of any ferromagnetic substance or a ferromagnetic composite.

The magnetic field of a bar magnet is strongest at either pole of the magnet. It is equally strong at the north pole compared with the south pole. The force is weaker in the middle of the magnet and halfway between the pole and the center.

If small compasses are used to map the magnetic field around a bar magnet, they will point in the direction away from the north pole of the magnet, toward the south pole of the magnet

3 0

3 years ago

A 750-kg automobile is moving at 26.2 m/s at a height of 5.00 m above the bottom of a hill when it runs out of gasoline. The car

Kisachek [45]

To solve this problem it is necessary to apply to the concepts related to energy conservation. For this purpose we will consider potential energy and kinetic energy as the energies linked to the body. The final kinetic energy is null since everything is converted into potential energy, therefore

Potential Energy can be defined as,

$PE = mgh$

Kinetic Energy can be defined as,

$K= \frac{1}{2} mv^2$

Now for Conservation of Energy,

$KE_i+PE_i = PE_f$

$\frac{1}{2}mv_i^2+mgh_1 = mgh_2$

$\frac{1}{2} (750kg) (26.2m/s)^2 + (750)(9.8)(5) = (750)(9.8)h_2$

$h_2 = 40.0224m$

Therefore the highets position the car reaches above the bottom of the hill is 40.02m

6 0

4 years ago

1-D Kinematics, Constant Acceleration After falling a distance of 45.0 m from the top of a building, a box is landing on the top

Mrrafil [7]

Answer:

Explanation:

Given

Object fall from a height of $s=45\ m$

Considering initial velocity to be zero i.e. $u=0$

using

$v^2-u^2=2as$

where v=final velocity

u=initial velocity

a=acceleration

s=displacement

$v^2-0=2(9.8)\cdot 45$

$v=29.69\ m/s\approx 29.7\ m/s$

(b)Average acceleration

After falling 45 m, object strike the car and comes to rest after covering a distance of 0.5 m

again using

$v'^2-u'^2=2as'$

here final velocity will be zero i.e. $v'=0$

initial velocity $u'=v$

$0-(29.7)^2=2\cdot a\cdot 0.5$

$a=-882.09\ m/s^2$

(c)time taken by it to stop

$v'=u'+a't$

$0=29.7-882.09\cdot t$

$t=0.034\ s$

5 0

3 years ago