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dem82 [27]
3 years ago
6

Polly is pushing a box across the floor with a force of 30 n. the force of gravity is –8 n, and the normal force is 8 n. which v

alue could describe the force of friction if polly could not move the box?–30 n–8 n8 n30 n
Physics
2 answers:
aliina [53]3 years ago
6 0

Answer:

Force of friction, F = -30 N

Explanation:

It is given that, Polly is pushing a box across the floor with a force of 30 N. The force of gravity is –8 N, and the normal force is 8 N.

We know that the frictional force is an opposing force. It always opposes the motion. It acts in the direction opposite to the direction of motion.

In this case, the box is pulled with a force of 30 N. So, the force of friction so that the box does not move will be 30 N but it acts in opposite direction.

So, the correct option is (a) " -30 N".

Rudiy273 years ago
3 0
It's -30N is the correct answer
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lorasvet [3.4K]

Net force on the car=F=4.8 x 10³ N

Explanation:

mass of car= 1.2 x 10³ Kg

initial velocity= Vi=0

Final velocity= Vf= 20 m/s

time = t= 5 s

Using kinematic equation,

Vf= Vi + at

20= 0 + a (5)

5 a=20

a= 20/5

a= 4 m/s²

Now force is given by F = ma

F= 1.2 x 10³ (4)

F=4.8 x 10³ N

7 0
3 years ago
Jon's bathtub is rectangular and its base is 18 ft2. (a) How fast is the water level rising if Jon is filling the tub at a rate
Kitty [74]

Answer:

The water level in the bath tub is rising at a rate of 0.0111 ft/s

Explanation:

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Area of base = 18 ft² (constant)

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V = 18h

(dV/dt) = 18 (dh/dt)

If (dV/dt) = 0.2 ft³/s

0.2 = 18 (dh/dt)

(dh/dt) = (0.2/18)

(dh/dt) = 0.0111 ft/s

Hope this Helps!!!

6 0
3 years ago
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A particle is confined to the x-axis between x = 0 and x = 1 nm. The potential energy U = 0 inside this region and U is infinite
DiKsa [7]

Answer:

Explanation:

According to heisenberg uncertainty Principle

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Given

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≥  . 5254 x ⁻²⁵

h / λ ≥  . 5254 x ⁻²⁵

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Katarina [22]

Answer:

i think its the 2nd law

Explanation:

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3 years ago
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Ray Of Light [21]

Explanation:

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Thanks

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4 years ago
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