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
lesantik [10]
3 years ago
9

A 4.2 kg sled is being pulled along a snow-covered road with a rope that exerts a horizontal force of 6.0 n and, at that moment,

is accelerating at 1.1 m/s2 on level ground with friction having no significant effect. what is the normal force on the sled?
Physics
2 answers:
Pavlova-9 [17]3 years ago
8 0
Normal force is equal to the formula of mg where m is the gravitational acceleration and g is the mass of the object. This is only applicable when the force is acting in the direction of the gravitational field and the  object is placed horizontally.So the formula is normal force = mg since the problem depicts what the statement is talking about.
So NF = mg= 9.8 m/s^2* 4.2kg= 41.16 N or 41 N
Stella [2.4K]3 years ago
6 0
<span>the body is moving horizontally, it doesnt matter watever kind of horizontal forces are acting.
 Therefore the normal force is equal to the weight
 N=mg=4.2*9.8=41N
 Note: the other data in the problem have no relevance
 answer
</span> the normal force on the sled is 41N 
You might be interested in
What is the speed of a wave on a string with a wavelength of 1.75 m and a frequency of 2.0 Hz
deff fn [24]

Answer:

V=3.5 m/s

Explanation:

V=(F)(W)

V=(2)(1.75)

V= 3.5 m/s

7 0
2 years ago
PLS HELP!!! A 1200-kg whale swims horizontally to the right at a speed of 6.0 m/s. It suddenly collides directly with a stationa
Fittoniya [83]

Answer:

7200 kg.m/s

Explanation:

According the law of conservation of linear momentum, the sum of momentum before and after collision are equal.

Using this principle, the sum of initial momentum will be given as p=mv where p is momentum, m is mass and v is velocity

Initial momentum

Mass of whale*initial velocity of whale + mass of seal*initial seal velocity

Since the seal is initially stationary, its velocity is zero. By substitution and taking right direction as positive

Initial momentum will be

1200*6+(280*0)=7200 kg.m/s

Since both initial and final momentum should be equal, hence the final momentum will also be 7200 kg.m/s

7 0
3 years ago
Can someone please help me with this physics question? I'm desperate!
Lelu [443]

Answer:

a) 2·√10 seconds

b) Linda should be approximately 30.6 meters

c) Jenny's speed at the 100-m mark is approximately 6.325 m/s

Explanation:

The speed with which Linda is running = 8.6 m/s

The point Jenny starts = The 80-m mark

The acceleration of Jenny = 1.0 m/s²

a) The time it takes Jenny to run from the 80-m mark to the 100-m mark, <em>t</em>, is given as follows

Δs = u·t + (1/2)·a·t²

Δs = Distance = 100-m - 80-m = 20-m

u = The initial velocity of Jenny = 0

a = Jenny's acceleration = 1.0 m/s²

∴ 20 = 0×t + (1/2) × 1 × t² = t²/2

20 = t²/2

t = √(20 × 2) = 2·√10

The time it takes Jenny to run from the 80-m mark to the 100-m mark = 2·√10 seconds

b) The distance Linda runs in t = 2·√10 seconds, d = v × t

Given that Linda's velocity, v = 8.6 m/s, we have;

d = 8.0 × 2·√10 = 16·√10

The distance Linda runs in t = 2·√10 seconds = 16·√10 meters ≈ 50.6 meters

Therefore, Linda should be approximately (50.6 - 20) meters = 30.6 meters behind Jenny when Jenny starts running

c) Jenny's speed at the 100 m mark is given as follows;

v = u + a·t

t = 2·√10 seconds, a = 1.0 m/s², u = 0

∴ v = 0×t + 1.0×2·√10 = 2·√10 ≈ 6.325

Jenny's speed at the 100-m mark ≈ 6.325 m/s

3 0
2 years ago
Sharks also swim in waters off the coast of Nova Scotia. When gray seals and harbor seals see sharks nearby, they must swim away
Vlada [557]
No. The seals are responding to a stimulus. 
6 0
3 years ago
Un the way to the moon, the Apollo astro-
kherson [118]

Answer:

Distance =  345719139.4[m]; acceleration = 3.33*10^{19} [m/s^2]

Explanation:

We can solve this problem by using Newton's universal gravitation law.

In the attached image we can find a schematic of the locations of the Earth and the moon and that the sum of the distances re plus rm will be equal to the distance given as initial data in the problem rt = 3.84 × 108 m

r_{e} = distance earth to the astronaut [m].\\r_{m} = distance moon to the astronaut [m]\\r_{t} = total distance = 3.84*10^8[m]

Now the key to solving this problem is to establish a point of equalisation of both forces, i.e. the point where the Earth pulls the astronaut with the same force as the moon pulls the astronaut.

Mathematically this equals:

F_{e} = F_{m}\\F_{e} =G*\frac{m_{e} *m_{a}}{r_{e}^{2}  } \\

F_{m} =G*\frac{m_{m}*m_{a}  }{r_{m} ^{2} } \\where:\\G = gravity constant = 6.67*10^{-11}[\frac{N*m^{2} }{kg^{2} } ] \\m_{e}= earth's mass = 5.98*10^{24}[kg]\\ m_{a}= astronaut mass = 100[kg]\\m_{m}= moon's mass = 7.36*10^{22}[kg]

When we match these equations the masses cancel out as the universal gravitational constant

G*\frac{m_{e} *m_{a} }{r_{e}^{2}  } = G*\frac{m_{m} *m_{a} }{r_{m}^{2}  }\\\frac{m_{e} }{r_{e}^{2}  } = \frac{m_{m} }{r_{m}^{2}  }

To solve this equation we have to replace the first equation of related with the distances.

\frac{m_{e} }{r_{e}^{2}  } = \frac{m_{m} }{r_{m}^{2} } \\\frac{5.98*10^{24} }{(3.84*10^{8}-r_{m}  )^{2}  } = \frac{7.36*10^{22}  }{r_{m}^{2} }\\81.25*r_{m}^{2}=r_{m}^{2}-768*10^{6}* r_{m}+1.47*10^{17}  \\80.25*r_{m}^{2}+768*10^{6}* r_{m}-1.47*10^{17} =0

Now, we have a second-degree equation, the only way to solve it is by using the formula of the quadratic equation.

r_{m1,2}=\frac{-b+- \sqrt{b^{2}-4*a*c }  }{2*a}\\  where:\\a=80.25\\b=768*10^{6} \\c = -1.47*10^{17} \\replacing:\\r_{m1,2}=\frac{-768*10^{6}+- \sqrt{(768*10^{6})^{2}-4*80.25*(-1.47*10^{17}) }  }{2*80.25}\\\\r_{m1}= 38280860.6[m] \\r_{m2}=-2.97*10^{17} [m]

We work with positive value

rm = 38280860.6[m] = 38280.86[km]

<u>Second part</u>

<u />

The distance between the Earth and this point is calculated as follows:

re = 3.84 108 - 38280860.6 = 345719139.4[m]

Now the acceleration can be found as follows:

a = G*\frac{m_{e} }{r_{e} ^{2} } \\a = 6.67*10^{11} *\frac{5.98*10^{24} }{(345.72*10^{6})^{2}  } \\a=3.33*10^{19} [m/s^2]

6 0
3 years ago
Other questions:
  • What is the purpose of setting a deadline for a goal?
    6·1 answer
  • You are walking on a beach and find a mystery piece of metal. You take it back to your lab and measure its mass to be 0.5 kg. In
    15·1 answer
  • Enter the expression 2gΔym−−−−−√, where Δ is the uppercase Greek letter Delta.
    9·1 answer
  • 1. What quantity of heat is required to raise
    14·1 answer
  • The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656 nm (red) and 486 nm (blue). Light f
    10·1 answer
  • Hey hi can someone help? ​
    5·2 answers
  • How large amount of energy is produced during the fission of uranium ​
    15·1 answer
  • You are locked inside the train car and want to get it moving to draw attention to your plight. There is effectively no friction
    5·1 answer
  • A man enters a tall tower, needing to know its height. He notes that a long pendulum extends from the ceiling almost to the floo
    14·1 answer
  • An object weighs 200N, what is its mass?​
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!