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
MAVERICK [17]
2 years ago
7

A student wearing frictionless in-line skates on a horizontal surface is pushed, starting from rest, by a friend with a constant

force of 60 N. How far must the student be pushed, so that her final kinetic energy is 300J?
Physics
2 answers:
grin007 [14]2 years ago
8 0

Answer:

Physics

Explanation:

Explanation:

We can use the Theorem of Work (W) and Kinetic Energy (K):

W=ΔK=Kf−Ki

it basically tells us that the work done on our system will show up as change in Kinetic Energy:

We know that the initial Kinetic Energy, Ki=12mv2i, is zero (starting from rest) while the final will be equal to 352J; Work will be force time displacement. so we get:

F⋅d=Ff

45d=352

and so:

d=35245=7.8≈8m

galben [10]2 years ago
3 0

Answer:

d= 352/45=7.8≈ 8m

Explanation

We can use the Theorem of Work (W) and Kinetic Energy (K):

W=ΔK=k <em>f</em> - k <em>i </em>, it is basically tells us that the work done on our system will show up as change in Kinetic Energy:We know that the initial Kinetic Energy, k<em>i</em> =1/2 <em>mv</em> 2/i, is zero (starting from rest) while the final will be equal to 352J; Work will be force time displacement. so we get: F . d = F<em>f</em>

45<em>d</em>= 352 and so d= 352/45=7.8 ≈ <em>8m</em>

You might be interested in
An old-fashioned LP record rotates at 33 1/3 RPM
Ksenya-84 [330]

Answer:

Part a) \frac{5}{9}\ \frac{rev}{sec}

Part b) \frac{9}{5}\ \frac{sec}{rev}

Explanation:

Part a) what is its frequency, in rev/s

we have that

An old-fashioned LP record rotates at 33 1/3 RPM

so

33\frac{1}{3}\ \frac{rev}{min}

Convert mixed number to an improper fraction

33\frac{1}{3}\ \frac{rev}{min}=\frac{33*3+1}{3}=\frac{100}{3}\ \frac{rev}{min}

Remember that

1\ min=60\ sec

Convert rev/min to rev/sec

\frac{100}{3}\ \frac{rev}{min}=\frac{100}{3}(\frac{1}{60})=\frac{100}{180}\ \frac{rev}{sec}

Simplify

\frac{5}{9}\ \frac{rev}{sec}

Part b) what is it period, in seconds

we know that

The period is the reciprocal of the frequency

therefore

the frequency is

\frac{9}{5}\ \frac{sec}{rev}

4 0
3 years ago
The term heredity is best defined as A. the ability of a species to reproduce. B. the hair color of a person's parents and grand
suter [353]

Answer:

I think it's D :)

6 0
3 years ago
What is the speed of the animal from 0-20s? <br><br> 50 m/s<br> 0.4 m/s<br> 20 m/s<br> 2.5 m/s
Shkiper50 [21]

Answer:

2.5 m/s

Explanation:

The speed of the animal is given by the ratio between the distance travelled by the animal and the time elapsed:

v=\frac{d}{t}

where d is the distance travelled and t the time elapsed. Note that this quantity is also equal to the slope of the curve.

In the time interval 0-20 s, we have

d = 50 m - 0 m = 50 m

t = 20 s - 0 s = 20 s

So, the speed is

v=\frac{50 m}{20 s}=2.5 m/s

3 0
2 years ago
Why is the weight of the ruler not include in the calculation of moment?​
Feliz [49]

Answer:

Since the distance between the pivot and its weight is zero, the moment of its weight about the pivot (= weight × 0) is zero. Hence, the weight of the ruler can be ignored.

Hope this helps:)

3 0
2 years ago
According to recent research, ice skaters are able to glide smoothly across the ice because _____.
nekit [7.7K]
In the blank should go of friction.
8 0
3 years ago
Other questions:
  • Question 5
    9·1 answer
  • Joe lives 100 miles away from Bill . What is Joes average speed if he reaches Bills home in50's?
    8·1 answer
  • A ball is given an initial velocity of 160ft/s straight up. Use g = -32ft/s^2
    9·1 answer
  • What is the central core of hair
    9·2 answers
  • The circuit has a 3 volt EMF and two ohm resistors. How much power in watts does this circuit draw? A) 4.5 , B) 24, C) 1.13 D) 2
    9·1 answer
  • Un repartidor de comida rápida entrega una pizza a una casa que se encuentra a 20 km de distancia y se demora 20 minutos en lleg
    7·1 answer
  • A person on a merry-go-round makes a complete revolution in about 3.17 s.
    11·1 answer
  • An echo is sound that returns to you after being reflected from a distant surface (e.g., the side of a cliff). Assuming that the
    5·2 answers
  • A 250 g blob of clay moves with a speed of 15 m/s towards a 400 g cart that is initially at rest. a). What is the momentum of th
    7·1 answer
  • Velocity ratio of a machine is 4 what does it mean​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!