A convection cell is BEST described as __

What is the acceleration of a 7 kg mass pushed by a 3.5 N force?

defon

Answer:

0.5m/s²

Explanation:

F =m x a

3.5 = 7 x a

a = 3.5 /7

a = 0.5m/s ²

4 0

3 years ago

A disk, initially rotating at 120 rpm, is slowed down with a constant acceleration of magnitude 4 rad s2. If the disk has diamet

andrey2020 [161]

Answer:

Explanation:

given,

ω₁ = 120 rpm

1 rpm = $\dfrac{2\pi }{60} rad/s$

$\omega_1 =120\times \dfrac{2\pi }{60}$ rad/s

= 12.56 rad/s

α = - 4 rad/s²

diameter of disk = 20 cm

final angular velocity = 0

t = $\dfrac{\omega_f-\omega_i}{\alpha}$

t = $\dfrac{0-(12.56)}{-4}$

t = 3.14 s.

2) $\theta = \omega_i t +\dfrac{1}{2} \alpha t^2$

= $12.56\times 3.14 +\dfrac{1}{2}\times (-4)\times 3.14^2$

= 19. 72 radians

3) total angular distance rotated

x = θ R

x = 19.72 × 0.1 = 1.97 m

x = 2 m

3 0

3 years ago

A truck passes point A on a straight level road with a constant velocity of 12 m/s. At the same instant, an automobile starts fr

REY [17]

Answer:

$t = 13.3 s$

Explanation:

Let the car will overtake the truck after time "t" seconds

so here we can say that after time "t" seconds the distance covered by the car will be same as that of distance covered by truck

So we have

$d_{car} = d_{truck}$

so we have

$d_{truck} = 12 t$

$d_{car} = \frac{1}{2}(1.8 m/s^2) t^2$

so now we have

$12 t = 0.9 t^2$

$t = 13.3 s$

7 0

3 years ago

A police car is driving north with a siren making a frequency of 1038 hz. Moops is driving north behind the police car at 12 m/s

Marianna [84]

Answer:

The police car is moving at 41.24 m/s.

Explanation:

To find the speed of the police car we need to use the Doppler equation:

$f = f_{0}(\frac{v + v_{r}}{v + v_{s}})$

Where:

v: is the speed of the sound = 343 m/s

$v_{r}$ : is the speed of the receiver = 12 m/s

$v_{s}$ : is the speed of the source =?

f: is the observed frequency = 959 Hz

f₀: is the emitted frequency = 1038 Hz

Both terms are positive in the fraction because the velocity of the sound is in the opposite direction to both velocities of the police car and the other car.

By solving the above equation for $v_{s}$ we have:

$v_{s} = \frac{f_{0}(v + v_{r})}{f} - v = \frac{1038(343 + 12)}{959} - 343 = 41.24 m/s$

Therefore, the police car is moving at 41.24 m/s.

I hope it helps you!

8 0

3 years ago

The weight lifter used a force of 980 N to raise the barbell over her head in 5.21 seconds. Approximately how much work did she

vesna_86 [32]

Answer:

That answer is 5105.8 J

Explanation:

5105.8 J

4 0

3 years ago

A convection cell is BEST described as ___.