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Olegator [25]
2 years ago
9

An object has a mass of 60 kg. It decelerates from 50 m/s to 20 m/s when a resultant force of 300 N acts on it. For how long doe

s the force act?
A 0.071 s
B 0.17 s
C 6.0 s
D 14 s​
Physics
1 answer:
Pavlova-9 [17]2 years ago
4 0
  • Force=300N
  • Mass=60kg

Find Acceleration

\\ \rm\longmapsto F=ma

\\ \rm\longmapsto a=\dfrac{F}{m}

\\ \rm\longmapsto a=\dfrac{-300}{60}

\\ \rm\longmapsto a=-5m/s^2

Now

  • u=50m/s
  • v=20m/s

Using 1st equation of kinematics

\\ \rm\longmapsto v=u+at

\\ \rm\longmapsto t=\dfrac{v-u}{a}

\\ \rm\longmapsto t=\dfrac{20-50}{-5}

\\ \rm\longmapsto t=\dfrac{-30}{-5}

\\ \rm\longmapsto t=6

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Explanation:

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8 0
3 years ago
Irina finds an unlabeled box of fine needles, and wants to determine how thick they are. A standard ruler will not do the job, a
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It is given that diameter of circular aperture is 14.7 cm so y_1=\frac{14.7}{2}=7.35 \ cm

Now putting all these value in eqn 3

d=\frac{1.22\lambda D}{y_1}

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8 0
2 years ago
A green light is submerged 2.70 m beneath the surface of a liquid with an index of refraction 1.31. What is the radius of the ci
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Answer:

The radius is  r = 3.1905 \ m

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Now the critical value is mathematically represented as

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Using SOHCAHTOA rule we have that

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8 0
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