a high school student ran the 100 meter dash in 12.20 seconds. find the velocity in meters per second and kilometers per hour.

6. When a positive charge is released and moves along an electric field line, it moves to a position of A) lower potential and l

Marysya12 [62]

Answer:

Since you would have to do work on the charge to bring it back to its original position, the charge moves to a position of lower potential and lower potential energy.

4 0

3 years ago

A crate of mass 9.2 kg is pulled up a rough incline with an initial speed of 1.58 m/s. The pulling force is 110 N parallel to th

kari74 [83]

Given that,

Mass = 9.2 kg

Force = 110 N

Angle = 20.2°

Distance = 5.10 m

Speed = 1.58 m/s

(A). We need to calculate the work done by the gravitational force

Using formula of work done

$W_{g}=mgd\sin\theta$

Where, w = work

m = mass

g = acceleration due to gravity

d = distance

Put the value into the formula

$W_{g}=9.2\times(-9.8)\times5.10\sin20.2$

$W_{g}=-158.8\ J$

(B). We need to calculate the increase in internal energy of the crate-incline system owing to friction

Using formula of potential energy

$\Delta U=-W$

Put the value into the formula

$\Delta U=-(-158.8)\ J$

$\Delta U=158.8\ J$

(C). We need to calculate the work done by 100 N force on the crate

Using formula of work done

$W=F\times d$

Put the value into the formula

$W=100\times5.10$

$W=510\ J$

We need to calculate the work done by frictional force

Using formula of work done

$W=-f\times d$

$W=-\mu mg\cos\theta\times d$

Put the value into the formula

$W=-0.4\times9.2\times9.8\cos20.2\times5.10$

$W=-172.5\ J$

We need to calculate the change in kinetic energy of the crate

Using formula for change in kinetic energy

$\Delta k=W_{g}+W_{f}+W_{F}$

Put the value into the formula

$\Delta k=-158.8-172.5+510$

$\Delta k=178.7\ J$

(E). We need to calculate the speed of the crate after being pulled 5.00m

Using formula of change in kinetic energy

$\Delta k=\dfrac{1}{2}m(v_{2}^2-v_{1}^{2})$

$v_{2}^2=\dfrac{2\times\Delta k}{m}+v_{1}^2$

Put the value into the formula

$v_{2}^2=\dfrac{2\times178.7}{9.2}+1.58$

$v_{2}=\sqrt{\dfrac{2\times178.7}{9.2}+1.58}$

$v_{2}=6.35\ m/s$

Hence, (A). The work done by the gravitational force is -158.8 J.

(B). The increase in internal energy of the crate-incline system owing to friction is 158.8 J.

(C). The work done by 100 N force on the crate is 510 J.

(D). The change in kinetic energy of the crate is 178.7 J.

(E). The speed of the crate after being pulled 5.00m is 6.35 m/s

8 0

3 years ago

What would the density of an object be with a mass of 0.8g

True [87]

The density of the object is 0.032 g/cm^3.

<h3>What is density?</h3>

The term density means the ratio of the mass to the volume of an object. Now we know that when an object is dense that it would sink to the bottom of a fluid.

Now given that;

Mass = 0.8 g

volume= 25 cm^3

Density = mass/volume

Density = 0.8 g / 25 cm^3

= 0.032 g/cm^3

Learn more about density:brainly.com/question/15164682

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MISSING PARTS

What is the density of an object having a mass of

0.8g and a volume of 25cm^3

4 0

2 years ago

A model rocket weighing 4.9 N launches from a pad. How much work does the little rocket engine do in the first 4 meters

USPshnik [31]

Answer:

Work done by the little rocket engine = 19.6 Joules.

Explanation:

We know that work = force x displacement.

Force = weight of rocket = 4.9 N

Displacement = 5 meter.

So work done by the little rocket engine = Weight of rocket x displacement.

Work done by the little rocket engine = 4.9 x 4 = 19.6 J

Work done by the little rocket engine = 19.6 Joules.

5 0

3 years ago

A material has a net electric charge because it _____.

Firdavs [7]

<span>C. has an excess or shortage of electrons.</span>

7 0

4 years ago

Read 2 more answers