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
abruzzese [7]
3 years ago
5

Sam, whose mass is 75 kg, straps on his skis and starts down a 50-m-high, 20 frictionless slope. A strong headwind exerts a hori

zontal force of 200 N on him as he skies. Use work and energy to find Sam’s speed at the bottom.
Physics
1 answer:
LenaWriter [7]3 years ago
3 0

Answer:

Explanation:

Sam mass=75kg

Height is 50m

20° frictionless slope

Horizontal force on Sam is 200N

According to the work energy theorem, the net work done on Sam will be equal to his change in kinetic energy.

Therefore

Wg - Ww =∆K.E

Note initial the body was at rest at top of the slope.

Then, ∆K.E is K.E(final) - K.E(initial)

K.E Is given as ½mv²

Since initial velocity is zero then, K.E(initial ) is zero

Therefore, ∆K.E=½mVf²

Wg is work done by gravity and it is given by using P.E formulas

Wg=mgh

Wg=75×9.8×50

Wg=36750J

Ww is work done by wind and it's is given by using formulae for work

Work=force × distance

Ww=horizontal force × horizontal distance

Using Trig.

TanX=opposite/adjacent

Tan20=h/x

x=h/tan20

x=50/tan20

x=137.37m

Then,

Ww=F×x

Ww=200×137.37

We=27474J

Now applying the formula

Wg - Ww =∆K.E

36750 - 27474 =½×75×Vf²

9276=37.5Vf²

Vf²=9275/37.5

Vf²= 247.36

Vf=√247.36

Vf=15.73m/s

You might be interested in
two plane mirrors inclined at an angle of 50 degree to each othe r a ray is incident on mirror1 then thedeviation x of ray after
Kipish [7]

The collapsed answer of Penchalreddy Badepalli is correct. The composition of two reflections via two mirror making an angle \alpha is equivalent to a single rotation by an angle 2\alpha, hence 2 * 60 deg = 120 deg. And turns is independent of the absolute orientation of the two mirrors in space and/or the direction of incidence of the incoming ray.

One could use elementary geometry to prove this (if you presume the direction of incidence is irrelevant imagine hitting the first mirror at 90 deg, then going retro right back along the normal to the first mirror, and follow the directions).

6 0
3 years ago
What is the meaning of Choreography for Aerobic Dance?
MakcuM [25]
Aerobic dance<span> has its foundation in </span>dance<span>-inspired movements. It is a cardiovascular workout set to music in a group </span>exercise<span> setting. You do not have to memorize </span>dance<span> moves, as the classes are taught by instructors who verbally tell and visually show the </span>choreography<span>.</span>
4 0
3 years ago
Please help will mark brainleist <br> ASAP
kiruha [24]

Answer:

B - Earth's path around the Sun

Explanation:

4 0
2 years ago
Read 2 more answers
Many of water's emergent properties, such as its cohesion, its high specific heat, and its high heat of vaporization, result fro
Bingel [31]

Answer:

Option 5.

Explanation:

Many of the properties of water like high specific heat, cohesion, high vaporization heat, etc can be contributed to the polar nature of water molecule.

Water being a polar molecule as it contains positively charged hydrogen and an electro-negative oxygen which results in uneven or non uniformity in sharing of electrons which leads to dipole formation and hence polarization of the molecule due to which it attracts its neighboring molecules.

This polar nature imparts the properties like cohesion, surface tension , adhesion, etc due to the presence of hydrogen bonds in water molecule.

3 0
3 years ago
A theory is a hyothesis that has been varified by multiple investigations. <br> True or false
irakobra [83]
<span>A theory is a hyothesis that has been varified by multiple investigations. 

true</span>
7 0
3 years ago
Other questions:
  • A VW beetle goes from zero to 27m/s in 7.6 seconds. What is the acceleration?
    5·1 answer
  • A box has a length of 20.0 cm, a width of 25.0 cm and its 30 cm tall. What is its volume using correct significant figures
    7·1 answer
  • Which describes how outer space, air, and glass affect the speed of light?
    14·1 answer
  • What are the Units of voltage?
    12·2 answers
  • A water pump with a power of 3.4 × 102 watts lifts water at the rate of 7.5 × 10-2 meters/second from a water tank. What is the
    8·1 answer
  • A wave travels at 1,500 m/s with a frequency of 5 hertz. What is its wavelength?
    11·1 answer
  • You have to make it balanced.
    7·1 answer
  • A hurricane that has winds between 74 and 95 miles per hour and causes some damage would be classified as a Category _______ sto
    7·1 answer
  • The compass uses a pendulous system to improve?
    11·1 answer
  • Entropy is how quickly things get messy.<br> O A. True<br> OB. False<br><br><br><br> Answer : False
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!