What is the current in a 160V circuit if the resistance is 2Ω?<br> V=<br> I=<br> R=

If the textbook weighs 19.6 newtons on venus,what is the strength of gravity on venus?

Greeley [361]

The correct answer is 8.9 m/s2

4 0

3 years ago

You can think of the work-kinetic energy theorem as the second theory of motion, parallel to Newton's laws in describing how out

kiruha [24]

Answer:

a) 4 289.8 J

b) 4 289.8 J

c) 6 620.1 N

d) 411 186.3 m/s^2

e) 6 620.1 N

Explanation:

Hi:

a)

The kinetic energy of the bullet is given by the following formula:

K = (1/2) m * v^2

With

m = 16.1 g = 1.61 x 10^-2 kg

v = 730 m/s

K = 4 289.8 J

b)

the work-kinetic energy theorem states that the work done on a system is the same as the differnce in kinetic energy of the same. Since the initial state of the bullet was at zero velocity (it was at rest) Ki = 0, therefore:

W = ΔK = Kf - Ki = 4 289.8 J

c)

The work done by a force is given by the line intergarl of the force along the trayectory of the system (in this case the bullet).

If we consider a constant force (and average net force) directed along the trayectory of the bullet, the work and the force will be realted by:

W = F * L

Where F is the net force and L is the length of the barrel, that is:

F = (4 289.8 J) / (64.8 cm) = (4 289.8 Nm) / (0.648 m) = 6620.1 N

d)

The acceleration can be found dividing the force by the mass:

a = F/m = (6620.1 N) /(16.1 g) = 411 186.3 m/s^2

e)

The force will have a magnitude equal to c) and direction along the barrel towards the exit

5 0

3 years ago

Johnson is dragging a bag on a ice surface. He pulls on the strap with a force of 112 N at an angle of 45° to the horizontal to

Nady [450]

Answer with Explanation:

We are given that

Force=F=112 N

$\theta=45^{\circ}$

Distance, $s=84 m$

Time, t=3.33 minutes

We have to find the work done by Johnson on the bag and the power generated by Johnson.

Work done, W= $Fscos\theta$

Using the formula

Work done, W= $112\times 84cos45=6652.46 J$

Power, P= $\frac{W}{t}=\frac{6652.46}{3.33\times 60}=33.3 watt$

Using 1 minute=60 s

Hence, the power generated by Johnson=33.3 watt

5 0

3 years ago

What would you need to know to calculate the angular momentum of a man on a Ferris wheel?

valentinak56 [21]

The angular momentum calculated with respect to the axis of rotation of an object is given by:
$L=mvr$
where m is the object's mass, v is its tangential speed, and r is its distance from the axis of rotation.

In case of a man on a Ferris wheel, we need to have these quantities in order to calculate his angular momentum. These quantities corresponds to:
- m, the mass of the man
- v, the tangential speed of the wheel at its edge
- r, the radius of the wheel

It is possible to calculate the angular momentum even if we don't know v, the tangential speed. In this case, we need to know at least the angular velocity $\omega$ (because from this relationship we can find the tangential speed: $v=\omega r$ ) or the period of rotation of the wheel, T (because we can find the angular velocity from it: $\omega= \frac{2 \pi}{T}$ ).

4 0

4 years ago

A certain satellite has a kinetic energy of 7.5 billion joules at perigee (closest to Earth) and 6.5 billion joules at apogee (f

Elena L [17]

Answer:

Work Done by the earth's gravitational force on the satellite as it travels from apogee to perigee is

W = F*D*Cos90° = 0

Explanation:

Although there is a change in the kinetic energy of the satellite at the apogee and perigee, the work done by the earth's gravitational force on the satellite is Zero.

W = F.D, F is the gravitational force, D is the displacement. Both F and D are vectors and perpendicular to each other. That is, the angle between F and D is 90°.

8 0

3 years ago

What is the current in a 160V circuit if the resistance is 2Ω? V= I= R=