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2 years ago

What is the minimum force required to life a 50-N load with one fixed pulley?'

1 answer:

8 0

One fixed pulley doesn't change the strength of the force that
pulls on the rope. The pulley only changes its direction. So,
to lift a 50-N load, you need to pull on the rope with at least 50-N .

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At a certain instant, coil A is in a 10-T external magnetic field and coil B is in a 1-T external magnetic field. Both coils hav

Neporo4naja [7]

Answer:

A) coil A

Explanation:

According to Faraday, Induced emf is given as;

E.M.F = ΔФ/t

ΔФ = BACosθ

where;

ΔФ is change in magnetic flux

θ is the angle between the magnetic field, B, and the normal to the loop of area A

A is the area of the loop

B is the magnetic field

From the equation above, induced emf depends on the strength of the magnetic field.

Both coils have the same area and are oriented at right angles to the field.

Coil A has a magnetic field strength of 10-T which is greater than 1 T of coil B, thus, coil A will have a greater emf induced in it.

7 0

3 years ago

Two stars of masses M and 6M are separated by a distance D. Determine the distance (measured from M) to a point at which the net

kotykmax [81]

Answer:

0.29D

Explanation:

Given that

F = G M m / r2

F = GM(6m) / (D-r)2

G Mm/r2 = GM(6m) / (D-r)2

1/r2 = 6 / (D-r)2

r = D / (Ö6 + 1)

r = 0.29 D

See diagram in attached file

7 0

2 years ago

What is the moment of inertia of the object starting from rest if it has a final velocity of 5.9 m/s? Express the moment of iner

Bogdan [553]

Answer:

The moment of inertia is I = 0.126*R^2*M

Explanation:

We can calculate the moment of inertia of an object that starts from rest and has a final velocity using the energy conservation equation, as follows:

Ek1 + Ep1 = Ek2 + Ep2, where

Ek1 = kinetic energy of the object before to roll down

Ep1 = potential energy of the object

Ek2 = kinetic energy when the object comes down

Ep2 = potential energy of the object at the bottom

We have the follow:

Ek1 = 0

Ep1 = M*g*h

Ek2 = ((I*w)/2) + ((M*v^2)/2)

Ep2 = 0

Replacing values:

0 + M*g*h = ((I*w)/2) + ((M*v^2)/2) + 0

where:

M = mass of the object

g = gravitational acceleration

I = moment of the inertia

w = angular velocity = v/R

h = height

M*g*h = ((1/2) * I * (v^2/R^2)) + ((M*v^2)/2)

M*9.8*2 = (I*(5.9^2)/(2*R^2)) + ((5.9^2 * M)/2)

19.6 * M = ((17.4*I)/R^2) + 17.4*M

Clearing I, we have:

I = 0.126*R^2*M

5 0

2 years ago

If the average pitcher is releasing the ball from a height of 1.8 m above the ground, and the pitcher's mound is 0.2 m higher th

neonofarm [45]

Answer: A. 2.0m above ground

Explanation:

Height of the pitcher from the floor of his mound = 1.8m

Height of the mound above the rest of the field = 0.2m

Since the height difference between the mound and the ground the catcher stands on = 0.2m and the pitcher throws the ball horizontally, then the catcher has to hold his glove at (1.8 + 0.2)m

above ground.

= 2.0m above ground (option A)

7 0

2 years ago

Em um centro de distribuição uma empilhadeira carrega uma caixa de 1000kg até o caminhão responsável pelo transporte desta carga

Yakvenalex [24]

Answer:

F = 592238.09 N

Explanation:

To find the mean force you first calculate the acceleration by using the following kinematic equation:

$v^2=v_o^2+2ax\\\\v_o=0m/s\\\\v=10km/h\\\\x=8.4m\\\\$

you do "a" the subject of the equation and replace the values of the other parameters:

$a=\frac{v^2}{2x}=\frac{10000m/s}{2(8.4m)}=595.23\frac{m}{s^2}$

next, the force, by using the second Newton law is:

$F=ma=(1000kg)(595.23\frac{m}{s^2})=595238.09\ N$

hence, the force is 592238.09 N

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TRANSLATION:

Para encontrar a força média, primeiro calcule a aceleração usando a seguinte equação cinemática:

você faz "a" o assunto da equação e substitui os valores dos outros parâmetros:

Em seguida, a força, usando a segunda lei de Newton, é:

portanto, a força é 592238.09 N

8 0

2 years ago