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An engineer is designing a small toy car that a spring will launch from rest along a racetrack. She wants to maximize the kinetic energy of the toy car when it launches from the end of a compressed spring onto the track, but she can make only a slight adjustment to the initial conditions of the car. The speed of the car just as it moves away from the spring onto the track is called the launch speed. Which of the following modifications to the car design would have the greatest effect on increasing the kinetic energy of the car? Explain your reasoning.Decrease the mass of the car slightly.
Increase the mass of the car slightly.
Decrease the launch speed of the car slightly.
Increase the launch speed of the car slightly.

Answers

Answer 1

Answer:

Answer:

we see that to increase the energy of the expensive we must increase the launch speed, since it increases quadratically

Explanation:

Kinetic energy is

K = ½ m v²

the speed of the expensive we can find it r

v² = v₀² + 2 a x

we can find acceleration with Newton's second law

F = m a

a = F / m

F= cte

substitute in the velocity equation

v² = v₀² + 2 F/m x

let's substitute in the kinetic energize equation

K = ½ m (v₀² + 2 F/m x)

K = ½ m v₀² + f x

we see that the kinetic energy depends on two tomines

in January in these systems the force for launching is constant, which is why decreasing the mass increases the speed of the vehicle and therefore increases the kinetic energy

As the launch speed increases the initial energy increases quadratically

we see that to increase the energy of the expensive we must increase the launch speed, since it increases quadratically

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a. A nucleus is made up of protons and neutrons. Protons have positive charges and neutrons have no charge. The strong nuclear force holds the nucleus together because it acts against another force inside the nucleus. What force is the strong nuclear force counteracting?

Answers

Answer:

The electromagnetic force tends to push the protons apart. (Like forces repel).

Explanation:

Answer:its the electromagnetic force

Explanation:

Protons are positive so repel themselves

Two charged particles attract each other with a force of magnitude F acting on each. If the charge of one is doubled and the distance separating the particles is also doubled, the force acting on each of the two particles has magnitude (a) F/2,
(b) F/4,
(c) F,
(d) 2F,
(e) 4F,
(f) None of the above.

Answers

Answer:

F/2

Explanation:

In the first case, the two charges are Q1 and Q2 and the distance between them is r. K is the Coulomb's constant

Hence;

F= KQ1Q2/r^2 ------(1)

Where the charge on Q1 is doubled and the distance separating the charges is also doubled;

F= K2Q1 Q2/(2r)^2

F2= 2KQ1Q2/4r^2 ----(2)

F2= F/2

Comparing (1) and (2)

The magnitude of force acting on each of the two particles is;

F= F/2

A typical automobile under hard braking loses speed at a rate of about 7.2 m/s2; the typical reaction time to engage the brakes is 0.55 s. A local school board sets the speed limit in a school zone such that all cars should be able to stop in 3.6 m. What maximum speed does this imply for a car in the school zone?

Answers

Answer:

4.3 m/s

Explanation:

a = rate at which the automobile loses speed = - 7.2 m/s²

v₀ = initial maximum speed of automobile

t' = reaction time for applying the brakes = 0.55 s

d = distance available for stopping the vehicle = 3.6 m

d' = distance traveled while applying the brakes = v₀ t' = (0.55) v₀

v = final speed after the vehicle comes to stop = 0 m/s

Using the equation

v² = v₀² + 2 a (d - d' )

0² = v₀² + 2 (- 7.2) (3.6 - (0.55) v₀)

v₀ = 4.3 m/s

The radius of a typical human eardrum is about 4.15 mm. Calculate the energy per second received by an eardrum when it listens to sound that is at the threshold of hearing, assumed to be 1.20E-12 W/m2

Answers

The energy per second received by an eardrum is $6.4884 * 10^(-17) watt$

Calculation of the energy per second;

The area should be

$= \pi r^2\n\n= 3.14 * 0.00415m\n\n= 5.407 * 10^(-5)m^2$

Now

The power should be

$= 1.2 * 10^(-12) * 5.407 * 10^(-5)\n\n= 6.4884 * 10^(-17) watt$

Learn more about the energy here: brainly.com/question/14338287

Answer:

Power energy per second will be equal to $6.4884* 10^(-17)watt$

Explanation:

We have given radius of human eardrum r = 4.15 mm = 0.00415 m

Intensity at threshold of hearing $I=1.2* 10^(-12)w/m^2$

Area is given by $A=\pi r^2=3.14* 0.00415^2=5.407* 10^(-5)m^2$

We know that power is given by $P=I* A=1.2* 10^(-12)* 5.407* 10^(-5)=6.4884* 10^(-17)watt$

So power energy per second will be equal to $6.4884* 10^(-17)watt$

The fundamental force that is responsible for beta decay is the: A) weak force. B) strong force. C) dark energy force. D) gravitational force E) electromagnetic force.

Answers

Answer:

A. Weak forces

Explanation:

The fundamental forces responsible for beta decay is the weak force. Weak forces are among the four fundamental forces of universe the electromagnetic, gravitational and strong forces. The weak forces are responsible for the decaying. The fundamental work of weak forces is covert neutron into proton and electron into neutrino. weak forces operate at very low distances as low as fermi meter.

Answer:

The answer is

dark energy force.

hope this helps u stay safe

Explanation:

Suppose that the speedometer of a truck is set to read the linear speed of the truck, but uses a device that actually measures the angular speed of the tires. If larger-diameter tires are mounted on the truck, will the reading on the speedometer be correct? If not, will the reading be greater than or less than the true linear speed of the truck? Why?

Answers

The measurement will be significantly affected.

Recall that the relationship between linear velocity and angular velocity is subject to the formula

$v = \omega r$ ,

Where r indicates the radius and $\omega$ the angular velocity.

As the radius increases, it is possible that the calibration is delayed and a higher linear velocity is indicated, that to the extent that the velocity is directly proportional to the radius of the tires.

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