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
Orlov [11]
3 years ago
12

A girl coasts down a hill on a sled, reaching

Physics
1 answer:
Simora [160]3 years ago
8 0

The sled travels a distance of 60.2 m before coming to rest.

The girl  reaches the ground with a speed <em>u</em>. She then travels forward on the hard icy snow, which has a coefficient of kinetic friction \mu _k . She comes to rest after travelling a distance <em>s</em> on the ground, due to the friction between the sled and the ground.

If the force of friction is <em>f</em> , the mass of the girl and the sled is <em>m</em> and the acceleration due to gravity is <em>g</em>, then,

f=\mu_kmg    .......(1)

This force exerts a decelerating force on the sled. If the deceleration of the sled is <em>a</em>, then,

f=ma   .......(2)

From equations (1) and (2),

f=\mu_kmg=-ma\\ a=-\mu_kg......(3)

Substitute 0.038 for  \mu _k and 9.81 m/s²for g.

a=-\mu_kg\\ =-(0.038)(9.81m/s^2)\\ =-0.3728m/s^2

Since the girl comes to rest, its final velocity is 0. Substitute 6.7 m/s for <em>u</em> and -0.3728m/s² for <em>a</em> in the equation of motion

v^2=u^2+2as

Solve for <em>s</em>.

v^2=u^2+2as\\ (0m/s)^2=(6.7m/s)^2+2(-0.3728m/s^2)s\\ s=\frac{(6.7m/s)^2}{2(0.3728m/s^2)} \\ =60.2m

Thus, the girl travels a distance of 60.2 m before coming to rest.

You might be interested in
A uniform meterstick of mass 0.20 kg is pivoted at the 40 cm mark. where should one hang a mass of 0.50 kg to balance the stick?
Tcecarenko [31]
The weight of the meterstick is:
W=mg=0.20 kg \cdot 9.81 m/s^2 = 1.97 N
and this weight is applied at the center of mass of the meterstick, so at x=0.50 m, therefore at a distance 
d_1 = 0.50 m - 0.40 m=0.10 m
from the pivot.
The torque generated by the weight of the meterstick around the pivot is:
M_w = W d_1 = (1.97 N)(0.10 m)=0.20 Nm

To keep the system in equilibrium, the mass of 0.50 kg must generate an equal torque with opposite direction of rotation, so it must be located at a distance d2 somewhere between x=0 and x=0.40 m. The magnitude of the torque should be the same, 0.20 Nm, and so we have:
(mg) d_2 = 0.20 Nm
from which we find the value of d2:
d_2 =  \frac{0.20 Nm}{mg}= \frac{0.20 Nm}{(0.5 kg)(9.81 m/s^2)}=0.04 m

So, the mass should be put at x=-0.04 m from the pivot, therefore at the x=36 cm mark.
4 0
3 years ago
For a standard production car, the highest road-tested acceleration ever reported occurred in 1993, when a Ford RS200 Evolution
Ann [662]

Answer:

a = 8.06 m/s²

Explanation:

The acceleration of this car can be found using the first equation of motion:

v_f = v_i + at\\\\a = \frac{v_f-v_i}{t}

where,

a = acceleration = ?

vf = final speed = 26.8 m/s

vi = initial speed = 0 m/s

t = time = 3.323 s

Therefore,

a = \frac{26.8\ m/s-0\ m/s}{3.323\ s}

<u>a = 8.06 m/s²</u>

3 0
2 years ago
Light waves are not mechanical waves. The Sun transmits light waves to Earth through __________ _________. *
Natasha2012 [34]
Electromagnetic waves?
3 0
3 years ago
Read 2 more answers
Scientists have documented that the current level of carbon dioxide in the atmosphere is _________
Leni [432]
<span>Scientists have documented that the current level of carbon dioxide in the atmosphere is increasing.</span>
7 0
3 years ago
The image shows a pendulum that is released from rest at point A. Shari tells her friend that no energy transformation occurs as
Masja [62]
Is  D    the  right  answer
6 0
3 years ago
Read 2 more answers
Other questions:
  • Charged beads are placed at the corners of a square in the various configurations shown in
    11·1 answer
  • What family does the fox come from?
    6·1 answer
  • The equation for density is a physical model true or false
    5·2 answers
  • What is the velocity of a quarter drooped from a towards after 10secounds
    12·1 answer
  • Which of the substances listed in the table on the first page would heat up more quickly if an equal amount
    8·1 answer
  • Kyle, a 95.0 kg football player, leaps straight up into the air (with no horizontal velocity) to catch a pass. He catches the 0.
    5·1 answer
  • There are two blocks: one large one initially at rest, and a smaller one, initially moving to the right withsome speed. The smal
    14·1 answer
  • A small hole is made at the bottom of a plastic cup. If it is filled with water and allowed to fall freely, will waterfall down
    14·2 answers
  • PLEASE HELP ILL MARK BRAINLIEST!!! A ball is initially thrown downwards with an initial speed of 20 m/s from the top of a 300 m
    11·1 answer
  • Consider an elevator with a table and a book on top of the table. The mass of the table is 10kg and the mass of the book is 2kg.
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!