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frosja888 [35]
3 years ago
7

A factory worker moves a 21.0 kg crate a distance of 4.50 m along a level floor at constant velocity by pushing horizontally on

it. The coefficient of kinetic friction between the crate and the floor is 0.300. What magnitude of force must the worker apply? Express your answer with appropriate units.
Physics
1 answer:
Alex_Xolod [135]3 years ago
5 0

Answer:

61.803 Newtons

Explanation:

m = Mass of crate = 21 kg

\mu = Coefficient of kinetic friction between the crate and the floor = 0.3

g = Acceleration due to gravity = 9.81 m/s²

Force

F=\mu mg

\\\Rightarrow F=0.3\times 21\times 9.81

\\\Rightarrow F=61.803\ N

So, the magnitude of force must the worker apply is 61.803 Newtons

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In the photo, a locomotive has broken through the wall of a train station. During the collision, what can be said about the forc
Pavlova-9 [17]

Answer:

Whether the force exerted by the locomotive on the wall was larger

Than the force the locomotive could exert on the wall.

Explanation:

The Newton's third law of motion States that every force have it's equal and opposite reaction force, whose magnitude is the same as the applied force. Therefore the magnitude of these opposite forces will be equal.

So we have;

F12=-F21

F12 is the force in a direction

-F21 is the force in the opposite direction.

Therefore we see that the magnitude of the force the locomotive exerts on the wall is equal to the one the wall exerts on the locomotive. Both magnitudes are equal but in opposite directions.

6 0
4 years ago
A spherical balloon is deflating at 10 cm3/s. At what rate is the radius changing when the volume is 1000π cm3 ? What is the rat
just olya [345]

Answer:

1.dr/dt=0.0096cm/s

2. dA/dt=2.19cm^2/s

Explanation:

A spherical balloon is deflating at 10 cm3/s. At what rate is the radius changing when the volume is 1000π cm3 ? What is the rate of change of surface area at this moment?

for this question, we need to analyze the parameters we know

V=volume of the spherical balloon 1000π cm3

volume of the sphere=\frac{4}{3} \pi r^{3}

1000π=4/3πr^3

dividing both sides by 4

250*3=r^3

r=9.08cm, the radius of the balloon

dv/dt=dv/dr*dr/dt...................................1

dv/dr  ,means

V=\frac{4}{3} \pi r^{3}

dv/dr=4*pi*r^2

dv/dt=10 cm3/s

from equ 1

10=4*pi*9.08^2*dr/dt

10=1036 dr/dt

dr/dt=10/1036

dr/dt=0.0096cm/s

2. to find the rate at which the area is changing we have,

dA/dt=dA/dr*dr/dt

area of a sphere is  4πr^2

differentiate a with respect to r, radius

dA/dr=8πr

dA/dt=8πr*0.0096

dA/dt=8*pi*9.08*0.0096

dA/dt=2.19cm^2/s

is the rate of change of the surface area

7 0
3 years ago
Develop a hypothesis for why one of the two types of soup should indeed be rolling down faster than the other. This hypothesis s
Eva8 [605]

Answer:

Assume two identical cans filled with two types of soup having same mass are rolling down on an inclined plane in same conditions. In terms of inertia different types of soup will indicate different viscosity. The higher viscosity fillings indicates more part of the soup mass is rotating together with the can’s body. This means that for the can with lower viscosity soup has a lower moment of inertia and the can with higher viscosity has higher moment of inertia while the same gravity makes them to roll.

incline angle = θ ; can's mass =  m ; Radius of the can's = R , Angular acceleration for Can 1 = α1 ; Angular acceleration for Can 2 = α2

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M1 rolling moment of Can 1

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as assumed T1 > T2

from the three equation (a), (b) & (c)

the α2 > α1

Angular acceleration of Can 2 is higher than Can 1. Already stated that Can 1 has more viscous soup as compared to Can 2.

7 0
3 years ago
All living things are made of one or more cells.<br> True<br> False
dimulka [17.4K]
False because their are single cell organisms
7 0
3 years ago
Read 2 more answers
What chemical reactions support all life on earth?
OlgaM077 [116]

Answer:

I’d say both anabolic and catabolic chemical reactions make life on Earth possible. Anabolic is the building up of molecules from atoms or small molecules and catabolic is the chemical reactions of breaking them down.

Explanation:

5 0
3 years ago
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