Ask question

Ask question

All categories

Dahasolnce [82]

2 years ago

12

a fan is rotating clockwise and its acceleration has a positive sign. is the angular velocity of the fan speeding up, slowing do

wn, or constant?

1 answer:

balu736 [363]2 years ago

5 0

Answer:

The angular velocity is slowing down.

Explanation:

By convention, if a rigid body is rotating clockwise, the angular velocity is negative.
If the angular acceleration has a positive sign, since the angular acceleration and the angular velocity have opposite signs, this means that the angular velocity is slowing down.

You might be interested in

Why do atoms do group 1 element lose electrons to form cations

Mrac [35]

Answer:

when a element of 1 group take part in reaction, its atom looses outer electron and form positively charged ions called Cation.

Explanation:

8 0

2 years ago

If a rock sample has a mass of 1.17 g and a volume of 0.33 cm3, what type of rock is it?

Marat540 [252]

The correct answer is diamond

5 0

3 years ago

Read 2 more answers

A block of mass 57.1 kg rests on a slope having an angle of elevation of 28.3°. If pushing downhill on the block with a force ju

stira [4]

Answer:

The coefficient is 0.90

Explanation:

Drawing a diagram makes thing easier, we will assume that the acceleration tends to zero because it start barely moving.

$-F_s+mg*sin(\theta)+F=0\\F_s=57.1kg*9.8m/s^2*sin(28.3)+177N\\F_s=442N\\F_s=\µ*N\\N=m*g*cos(\theta)\\N=57.1*9.8*cos(28.3)=493N\\\\\µ=\frac{442N}{493N}=0.90$

3 0

2 years ago

One difference between a solar flare and a CME is that a solar flare is composed of ___________, while a CME is composed of ____

JulsSmile [24]

Answer:

magnetic energy (proton) and magnetic plasma.

Explanation:

The solar fare consists of bright light that occurs in various wavelengths and is observed at the surface.

They are not as strong as compared to the coronal mass ejection or CME. The solar fares consist of 10²² joules, while the plasma is ejected from the solar corona and can be clearly seen from a distance.

The Solar flares represent an atmospheric disturbance and plasms are the medium for the growth and development of solar flare and lead to solar activity.

6 0

2 years ago

Consider a father pushing a child on a playground merry-go-round. The system has a moment of inertia of 84.4 kg.m^2. The father

Sophie [7]

Answer:

Explanation:

Given that:

the initial angular velocity $\omega_o = 0$

angular acceleration $\alpha$ = 4.44 rad/s²

Using the formula:

$\omega = \omega_o+ \alpha t$

Making t the subject of the formula:

$t= \dfrac{\omega- \omega_o}{ \alpha }$

where;

$\omega = 1.53 \ rad/s^2$

∴

$t= \dfrac{1.53-0}{4.44 }$

t = 0.345 s

b)

Using the formula:

$\omega ^2 = \omega _o^2 + 2 \alpha \theta$

here;

$\theta$ = angular displacement

∴

$\theta = \dfrac{\omega^2 - \omega_o^2}{2 \alpha }$

$\theta = \dfrac{(1.53)^2 -0^2}{2 (4.44) }$

$\theta =0.264 \ rad$

Recall that:

2π rad = 1 revolution

Then;

0.264 rad = (x) revolution

$x = \dfrac{0.264 \times 1}{2 \pi}$

x = 0.042 revolutions

c)

Here; force = 270 N

radius = 1.20 m

The torque = F * r

$\tau = 270 \times 1.20 \\ \\ \tau = 324 \ Nm$

However;

From the moment of inertia;

$Torque( \tau) = I \alpha \\ \\ Since( I \alpha) = 324 \ Nm. \\ \\ Then; \\ \\ \alpha= \dfrac{324}{I}$

given that;

I = 84.4 kg.m²

$\alpha= \dfrac{324}{84.4} \\ \\ \alpha=3.84 \ rad/s^2$

For re-tardation; $\alpha=-3.84 \ rad/s^2$

Using the equation

$t= \dfrac{\omega- \omega_o}{ \alpha }$

$t= \dfrac{0-1.53}{ -3.84 }$

$t= \dfrac{1.53}{ 3.84 }$

t = 0.398s

The required time it takes= 0.398s

5 0

2 years ago