1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MAXImum [283]
3 years ago
8

Your backpack has a mass of 8 kg. You lift it from the ground to a height of

Physics
1 answer:
motikmotik3 years ago
3 0

Answer:

the answer will be 5.6 j..

hope you like the answer.....

You might be interested in
8. An unpowered flywheel is slowed by a constant frictional torque. At time t = 0 it has an angular velocity of 200 rad/s. Ten s
allsm [11]

Answer:

a) \omega = 50\,\frac{rad}{s}, b) \omega = 0\,\frac{rad}{s}

Explanation:

The magnitude of torque is a form of moment, that is, a product of force and lever arm (distance), and force is the product of mass and acceleration for rotating systems with constant mass. That is:

\tau = F \cdot r

\tau = m\cdot a \cdot r

\tau = m \cdot \alpha \cdot r^{2}

Where \alpha is the angular acceleration, which is constant as torque is constant. Angular deceleration experimented by the unpowered flywheel is:

\alpha = \frac{170\,\frac{rad}{s} - 200\,\frac{rad}{s} }{10\,s}

\alpha = -3\,\frac{rad}{s^{2}}

Now, angular velocities of the unpowered flywheel at 50 seconds and 100 seconds are, respectively:

a) t = 50 s.

\omega = 200\,\frac{rad}{s} - \left(3\,\frac{rad}{s^{2}} \right) \cdot (50\,s)

\omega = 50\,\frac{rad}{s}

b) t = 100 s.

Given that friction is of reactive nature. Frictional torque works on the unpowered flywheel until angular velocity is reduced to zero, whose instant is:

t = \frac{0\,\frac{rad}{s}-200\,\frac{rad}{s} }{\left(-3\,\frac{rad}{s^{2}} \right)}

t = 66.667\,s

Since t > 66.667\,s, then the angular velocity is equal to zero. Therefore:

\omega = 0\,\frac{rad}{s}

7 0
3 years ago
A particle of mass m collides with a second particle of mass m. Before the collision, the first particle is moving in the x-dire
oee [108]

Answer:

a) v, v

b) 2mv^2

c) Elastic collion

Explanation:

(a) The velocity of the second particle after the collision is (v2x,v2y)=(v,−v).  From momentum conservation in x-direction

Here x, y represent direction.They are not variable. 1 and 2 represent before and after.

2vm=v1xm+v2xm, we find v1x=v.

From momentum conservation in y-direction

0 =v1ym+v2ym, we findv1y=v.

(b) By energy conservation principle

Before: K=1/2m(2v)^2=2mv^2.

After: K=1/2m(v^2(1x)+v^2(1y))+12m(v22x+v22y)=2mv^2

(c) The collision is elastic

6 0
3 years ago
PLEASE HELP ME.....WILL MARK BRAINLIEST ANSWER
schepotkina [342]
A) gases particles are far apart
8 0
3 years ago
Read 2 more answers
I just need the answer
Archy [21]

Answer:

I'll try to help which grade are you?

7 0
2 years ago
Vygotsky’s theory of cognitive development states that an individual constructs knowledge primarily through interaction with imp
defon

Answer:

false

Explanation:

trust me i j took the test

4 0
3 years ago
Read 2 more answers
Other questions:
  • Calculate the average velocity of a dancer who moves 5 m toward the left of the stage over the course of 15 s. ** Velocity = dis
    11·1 answer
  • In astronomy, the term perihelion refers to the point in the orbit of an asteroid, comet, or planet when it is closest to the su
    15·1 answer
  • If the diameter of a radar dish is doubled, what happens to its resolving power assuming that all other factors remain unchanged
    14·1 answer
  • A block slides forward 4.73 m while being pulled back by a 39.7 N force at 142° from the direction of motion. How much work does
    13·1 answer
  • The __________muscle raises the eyebrows and causes wrinkles across the forehead.
    10·1 answer
  • What electromagnetic waves are used in these applications?
    6·1 answer
  • I need help with an assignment a need help can someone help me SCIENCE.
    7·1 answer
  • Lab number 14: sudden stops hurt newtons first law
    11·1 answer
  • Riders on a ferris wheel move in a circle with a speed of 4.0 m/s. As they go around, they
    7·1 answer
  • A cylinder with a radius of 1.8 cm is floating in water as shown below. The mass of the cylinder is 1.80 kg. Calculate the depth
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!