All categories

4 years ago

At what speed must a 950-kg subcompact car be moving to have the same kinetic energy as a 3.2×104−kg truck going 20 km/h?

Physics

1 answer:

Ostrovityanka [42]4 years ago

6 0

Answer:

950-kg subcompact car be moving to have the same kinetic energy of truck at 116.08 km/hr

Explanation:

Kinetic energy of body with mass m and moving at velocity v is given by

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

KE of truck $= \frac{1}{2}*3.2*10^4*20^2$

KE of subcompact car $= \frac{1}{2}*950*v^2$

Equating

$\frac{1}{2}*3.2*10^4*20^2= \frac{1}{2}*950*v^2\\ \\ v=116.08 km/hr$

So 950-kg subcompact car be moving to have the same kinetic energy of truck at 116.08 km/hr

You might be interested in

Which statement accurately describes the chemical symbol of an element?

Mekhanik [1.2K]

The chemical symbol always begins with a capital letter.

8 0

3 years ago

Read 2 more answers

What is the SI unit of electric charge

shusha [124]

Answer:

The SI unit for electric chargeis the C (which is the abbreviation of Coulomb}

Explanation:

The SI unit for electric chargeis the Coulomb. The letter used is the C.

1 C = 1 As

4 0

4 years ago

Tarzan and Jane. Because of your concern that incorrect science is being taught to children when they watch cartoons on TV, you

creativ13 [48]

Answer:

The maximum height Tarzan and Jane can swing as a fraction of her initial heigh is ⅓h

Explanation:

Let

m = Mass of Tarzan

M = Mass of Jane

Given

M = 2m

To calculate the maximum height Tarzan and Jane can swing, we make use of the potential energy at their initial and final position.

Reason being that;

At both the initial and final position, velocity is 0, so there's no kinetic energy.

And the potential energy remains the same (i.e constant) at any given point in the system.

Using P.E = mgh.

At initial position, PE1 = mgh

At final position, PE2 = (m + M)gH.

Where h and H represent the initial and final heights.

m + M is the new weight after Jane and Tarzan swing

Equating PE1 to PE2

mgh = (m + M)gH

By substituton (M = 2m)

mgh = (m + 2m)gH

mgh = 3mgH

Make H the subject of the formula

H = mgh/3mg

H = ⅓h

Hence, the maximum height Tarzan and Jane can swing as a fraction of her initial heigh is ⅓h

From the question, the new height looks to be about ½ that of Jane's original position; i.e. ½h

The calculated height is smaller than what the cartoon is showing;

We can conclude that the cartoon is wrong.

4 0

3 years ago

In the simplified version of Kepler's third law, P 2 = a3, the units of the orbital period P and the semimajor axis a of the ell

Orlov [11]

Answer:

The units of the orbital period P is years and the units of the semimajor axis a is astronomical units.

Explanation:

P² = a³ is the simplified version of Kepler's third law which governs the orbital motion of large bodies that orbit around a star. The orbit of each planet is an ellipse with the star at the focal point.

Therefore, if you square the year of each planet and divide it by the distance that it is from the star, you will get the same number for all the other planets.

Thus, the units of the orbital period P is years and the units of the semimajor axis a is astronomical units.

8 0

3 years ago

The largest hailstone every measured fell in Vivian, Nebraska in 2010. The circumference of that hailstone was 19 inches. Using

Crazy boy [7]

Answer:

6.04788 in

$115.82654\ in^3$