Ask question

Ask question

All categories

Diano4ka-milaya [45]

3 years ago

8

A car weighing 8000N is traveling at 45 m/s on a perfectly flat, frictionless road. If the driver slams on the brakes, how far w

ill thw car slide before it comes to a stop?

1 answer:

laila [671]3 years ago

3 0

Without friction, the car cannot stop...

You might be interested in

Compared to Earth's moon, the moons of Mars are

Mice21 [21]

I think is b I think

7 0

3 years ago

Transformer is used in rectifier step up and step down voltage?<br>

tensa zangetsu [6.8K]

Answer:

While the use of the type of transformer in a rectifier depends on the voltage requirement or to meet desired operating conditions, a step-down transformer is used mainly to reduce the voltage. It is used to bring the high AC voltage level to a reasonable value or the desired output voltage.

Explanation:

Hope it helps

Correct me if Im wrong

3 0

2 years ago

Calculate the amount of heat (in kj) required to raise the temperature of a 79.0 g sample of ethanol from 298.0 k to 385.0 k. th

earnstyle [38]

We are given with the specific heat capacity of ethanol, the mass of the sample and the temperature change to determine the total amount of heat to raise the temperature. The formula to be followed is H = mCpΔT. Upon subsituting, H = 79 g * 2.42 J/gC *(385-298)C = 16.63 kJ

7 0

4 years ago

The mass of a moving object increases, but its speed stays the same. What happens to the kinetic energy of the object as a resul

ozzi

The correct answer is
B It increases.

In fact, the kinetic energy of a moving object is given by
$K= \frac{1}{2}mv^2$
where m is the mass of the object and v is its speed. We see that the kinetic energy is proportional to the mass and proportional to the square of the speed: in this problem, the speed of the object remains the same, while its mass increases, therefore the kinetic energy will increase as well.

5 0

4 years ago

Read 2 more answers

The engine in an imaginary sports car can provide constant power to the wheels over a range of speeds from 0 to 70 miles per hou

Mama L [17]

A) Time needed: 6.24 s

B) Time needed: 2.86 s

Explanation:

A)

In this part, we are told that the power if the engine is constant. The power of the engine is given by

$P=\frac{W}{t}$

where

W is the work done

t is the time

This means that the power of the engine is proportional to the work done, and therefore, to the kinetic energy of the car:

$P=\frac{\frac{1}{2}mv^2}{t}=const.$

where m is the mass of the car and v its velocity.

SInce power is constant, we can write:

$\frac{\frac{1}{2}mv_1^2}{t_1^2}=\frac{\frac{1}{2}mv_2^2}{t_2}$

where:

$t_1=1.40 s$ is the time the car needs to accelerates to $v_1=28.0 mph$

$t_2$ is the time the car needs to accelerate to $v_2=57.0 mph$

Therefore, solving for $t_2$ ,

$t_2 = \frac{v^2}{u^2}t_1=\frac{57^2}{28^2}(1.40)=6.24 s$

B)

First of all, we have to calculate the acceleration of the car. We can do it using the following equation:

$a=\frac{v-u}{t}$

where:

u = 0 is the initial velocity

$v=28.0 mph \cdot \frac{1609 m/mi}{3600 s/h}=12.5 m/s$ is the final velocity

t = 1.40 s is the time elapsed

Substituting, we find the acceleration:

$a=\frac{12.5-0}{1.40}=8.9 m/s^2$

In this part, we are told that the force exerted by the engine is constant: according to Newton's second law, acceleration is proportional to the force,

$F=ma$

This means that the acceleration is also constant.

Now we want to find how long the car takes to accelerate to a final velocity of

$v=57.0 mph \cdot \frac{1609}{3600}=25.5 m/s$

From an initial velocity of

u = 0

Using again the same suvat equation, and using the acceleration we found previously, we find:

$t=\frac{v-u}{a}=\frac{25.5-0}{8.9}=2.87 s$

Learn more about accelerated motion:

brainly.com/question/9527152

brainly.com/question/11181826

brainly.com/question/2506873

brainly.com/question/2562700

About power:

brainly.com/question/7956557

#LearnwithBrainly

6 0

4 years ago