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3 years ago

13

If an asteroid were going to impact Earth, would you prefer to know in advance or let the NEO remain a mystery until impact? Why

?

1 answer:

ivanzaharov [21]3 years ago

6 0

I would like to know in advance

You might be interested in

An object is spun around in circular motion such that its period is 0.2 seconds.

kherson [118]

Answer:

a. 5 Hertz

b. 35 rotations

Explanation:

a. Frequency is given by $f=\frac{1}{T}$ where $T$ is the period, in seconds. Given that $T=0.2$ , the frequency of this object's rotation is:

$f=\frac{1}{T}=\frac{1}{0.2}=\boxed{5\text{ Hz}}$

b. Since one rotation, or period, is completed in 0.2 seconds, divide the amount of time (7 seconds) by the time it takes to complete one revolution (0.2 seconds):

$\frac{7}{0.2}=\boxed{35 \text{ rotations}}$

3 0

2 years ago

A 61.6 turns circular coil with radius 4.44 cm and resistance 2.34 Ω is placed in a magnetic field directed perpendicular to the

Setler [38]

Answer:

Induced emf is 0.324 V

Explanation:

We have,

Number of turns, n = 61.6

Radius of circular coil, r = 4.44 cm

Resistance of coil, R = 2.34 Ω

The magnitude of the magnetic field varies in time according to the expression :

$B=a_1t+a_2t^2$

$a_1=0.0411\\\\a_2=0.044$

The magnitude of the induced emf in the coil is given by :

$\epsilon=\dfrac{d\phi}{dt}\\\\\epsilon=\dfrac{d(NBA)}{dt}\\\\\epsilon=NA\dfrac{dB}{dt}$

$\epsilon=\pi r^2\dfrac{dB}{dt}$

At t = 9.21 s,

$\dfrac{dB}{dt}=(0.0411+2\times 0.044 \times 9.21)\\\\\dfrac{dB}{dt}=0.851\ T/s$

$\epsilon=61.6\times \pi \times (4.44 \times 10^{-2})^2\times 0.851$

$\epsilon=5.27\times 10^{-3}\ V$

So, the magnitude of the induced emf in the coil is 0.324 V

5 0

4 years ago

Which type of wires (copper, aluminum, or string) are ferromagnetic metals?

sp2606 [1]

Answer:

Copper isn't ferromagnetic,

Aluminum isn't ferromagnetic,

String has a ferromagnetic property

So in conclusion:

The answer is strings :)

8 0

3 years ago

A scientist heated a tank containing 50 g of water. The specific heat of water is 4.18 J/gºC. The temperature of the water incre

butalik [34]

Answer: a) 2,508

Explanation:

6 0

3 years ago

Se deja caer una pelota inicialmente en reposo desde una altura de 50m sobre el nivel del suelo. ¿cuanto tiempo requiere para ll

umka2103 [35]

Answer:

a) t = 3.2 s

b) $v_{f} = -32 m/s$

Explanation:

a) El tiempo requerido para llegar al suelo se puede calcular usando la siguiente fórmula:

$t = \sqrt{\frac{2y_{0}}{g}}$

En donde:

$y_{0}$ : es la altura inicial = 50 m

g: es la gravedad = 10 m/s²

$t = \sqrt{\frac{2y_{0}}{g}} = \sqrt{\frac{2*50 m}{10 m/s^{2}}} = 3.2 s$

Entonces, el tiempo requerido para llegar al suelo es 3.2 s.

b) La rapidez de la pelota justo antes del choque es el siguiente:

$v_{f} = v_{0} - gt$

En donde:

$v_{0}$ : es la velocidad inicial = 0 (dado que se deja caer en resposo)

$v_{f} = v_{0} - gt = 0 - 10 m/s^{2}*3.2 s = -32 m/s$

Por lo tanto, la rapidez de la pelota justo en el momento anterior del choque es -32 m/s (el signo negativo es porque la pelota está cayendo).

Espero que te sea de utilidad!

6 0

3 years ago