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
SpyIntel [72]
2 years ago
6

I need help with questions b and d, that’s all. Thank you.

Physics
1 answer:
Mkey [24]2 years ago
7 0

b).  The power depends on the RATE at which work is done.  

Power = (Work or Energy) / (time)

So to calculate it, you have to know how much work is done AND how much time that takes.

In part (a), you calculated the amount of work it takes to lift the car from the ground to Point-A.  But the question doesn't tell us anywhere how much time that takes.  So there's NO WAY to calculate the power needed to do it.

The more power is used, the faster the car is lifted.  The less power is used, the slower the car creeps up the first hill.  If the people in the car have a lot of time to sit and wait, the car can be dragged from the ground up to Point-A with a very very very small power ... you could do it with a hamster on a treadmill.  That would just take a long time, but it could be done if the power is small enough.

Without knowing the time, we can't calculate the power.

...

d).  Kinetic energy = (1/2) · (mass) · (speed squared)

On the way up, the car stops when it reaches point-A.  

On the way down, the car leaves point-A from "rest".

WHILE it's at point-A, it has <u><em>no speed</em></u>.  So it has no (<em>zero</em>) kinetic energy.

You might be interested in
The cube with 2.00m wide and 2.00m long and 2.00m high has a weight of 960.00 N what pressure does it exert
andre [41]
2m X 2m = 4m ^2
960n / 4 = 240pa
3 0
3 years ago
3. The direction of the centripetal force acting on a ball on a string being spun in a circle around a person is
ruslelena [56]

D. center seeking. Good Luck

4 0
3 years ago
Read 2 more answers
How can spectroscopy and infrared technology be useful in space?
olchik [2.2K]

Answer:

B

Explanation:

Spectroscopy measures electromagnetic radiation.

3 0
3 years ago
Zero, a hypothetical planet, has a mass of 5.8 x 1023 kg, a radius of 2.7 x 106 m, and no atmosphere. a 10 kg space probe is to
Tom [10]
To answer these questions just use the equations for potential energy using the mass and heights described. the potential energy at the prescribed heights = the initial kinetic energy required to reach that height.

Make sure you calculate the force of gravity on the surface using the radius of the planet.
5 0
3 years ago
IP The x and y components of a vector r⃗ are rx = 16 m and ry = -8.5 m , respectively
fiasKO [112]

as it is given that

r_x = 16 m

r_y = -8.5 m

now we will have

\vec r = 16 \hat i - 8.5 \hat j

now the magnitude of this vector is given as

|r| = \sqrt{16^2 + 8.5^2}

|r| = 18 m

now to find the direction we can use

tan\theta = \frac{r_y}{r_x}

tan\theta = \frac{-8.5}{16}

\theta = tan^{-1}(-0.53)

\theta = - 28^0

4 0
3 years ago
Other questions:
  • Which statement correctly stated kepler's 3rd law of planetary motion?
    12·2 answers
  • An atomic nucleus is composed of A) protons. B) protons and neutrons. C) protons and electrons. D) protons, neutrons, and electr
    15·2 answers
  • You are standing on a skateboard, initially at rest. a friend throws a very heavy ball towards you. you can either catch the obj
    10·1 answer
  • What type of machine is wire cutter pliers?
    7·2 answers
  • A toaster using a Nichrome heating element operates on 120 V. When it is switched on at 28 ∘С, the heating element carries an in
    14·1 answer
  • The discussion of the electric field between two parallel conducting plates, in this module states that edge effects are less im
    12·1 answer
  • Could a nucleus that has one proton but no neutrons exist?
    15·1 answer
  • Any fracture or system of fractures along which Earth moves is known as a
    15·1 answer
  • A railroad car moving at a speed of 3.46 m/s overtakes, collides and couples with two coupled railroad cars moving in the same d
    13·1 answer
  • A stone was dropped off a cliff and hit the ground with a speed of 88 ft/s. What is the height (in feet) of the cliff
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!