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3 years ago

a red kangaroo can hop at speeds of 65 km/hr. how much time will it take the kangaroo to hop 0.25 km at that speed?

Physics

1 answer:

daser333 [38]3 years ago

3 0

Time = (distance) / (speed)

Time = (0.25 km) / (65 km/hr)

Time = 0.00385 hour

(That's 13.85 seconds.)

Better way:

Distance = 0.25 km

Distance = 250 meters

Speed = (65 km/hr) x (1000 m/km) x (1 hr/3600 sec)

Speed = 18.06 m/sec

Time = (250 m) / (18.06 m/s)

Time = 13.85 seconds

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Two positive charges of 20 micro coulomb and 100 micro coulomb and the distance between them is 150cm.What will be the electrica

Roman55 [17]

Answer:

0.8 N

Explanation:

From coulomb's law,

Formula:

F = kqq'/r²........................ Equation 1

Where F = Force of repulsion, k = coulomb's constant, q = first positive charge, q' = second positive charge, r = distance between the charge.

Given: q = 20 μC = 20×10⁻⁶ C, q' = 100 μC = 100×10⁻⁶ C, r = 150 cm = 1.5 m.

Constant: k = 9×10⁹ Nm²/C²

Substitute these values into equation 1

F = (20×10⁻⁶ )( 100×10⁻⁶)(9×10⁹)/1.5²

F = 1800×10⁻³/2.25

F = 1.8/2.25

F = 0.8 N

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3 years ago

What can i do to recycle?

mafiozo [28]

Answer:

You could throw away the following items:

Mixed paper: Newspaper, magazine, junk mail, cardboard, frozen food packaging, wrapping paper, paper bags, etc.

Cans: aluminum, foil, tin, steal, aerosol (empty without pressure) and metal food trays. ...

Unbroken glass: Wine bottles, bottles and jars.

Plastic: Rigid containers like milk jugs, shampoo or water bottles.

Hope this helped

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3 years ago

Two students are watching a person riding a skateboard up and down a ramp. Each student shares what they think about the energy

Setler79 [48]

Answer:

The correct option is;

Raymond: I think the skateboarder has the same total energy at all points on the ramp

Explanation:

The total energy, also known as the total mechanical energy, is the sum of the kinetic and potential energies of the skateboarder

Given that the potential energy is the energy gained due to elevation, the maximum potential energy is obtained at the top of the ramp, while the maximum kinetic energy, which is the energy due to motion, is at the bottom of the ramp where the skateboarder moves fastest.

However, by the energy conservation principle, the kinetic energy of he skateboarder comes from the conversion of the potential energy, such that the total energy is the same at any particular point on the ramp.

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3 years ago

An electron moves at 0.130 c as shown in the figure (Figure 1). There are points: A, B, C, and D 2.10 μm from the electron.

Olegator [25]

Hi there!

We can use Biot-Savart's Law for a moving particle:
$B= \frac{\mu_0 }{4\pi}\frac{q\vec{v}\times \vec{r}}{r^2 }$

B = Magnetic field strength (T)
v = velocity of electron (0.130c = 3.9 × 10⁷ m/s)

q = charge of particle (1.6 × 10⁻¹⁹ C)

μ₀ = Permeability of free space (4π × 10⁻⁷ Tm/A)

r = distance from particle (2.10 μm)

There is a cross product between the velocity vector and the radius vector (not a quantity, but specifies a direction). We can write this as:

$B= \frac{\mu_0 }{4\pi}\frac{q\vec{v} \vec{r}sin\theta}{r^2 }$

Where 'θ' is the angle between the velocity and radius vectors.

a)
To find the angle between the velocity and radius vector, we find the complementary angle:

θ = 90° - 60° = 30°

Plugging 'θ' into the equation along with our other values:

$B= \frac{\mu_0 }{4\pi}\frac{q\vec{v} \vec{r}sin\theta}{r^2 }\\\\B= \frac{(4\pi *10^{-7})}{4\pi}\frac{(1.6*10^{-19})(3.9*10^{7}) \vec{r}sin(30)}{(2.1*10^{-5})^2 }$

$B = \boxed{7.07 *10^{-10} T}$

b)
Repeat the same process. The angle between the velocity and radius vector is 150°, and its sine value is the same as that of sin(30°). So, the particle's produced field will be the same as that of part A.

In this instance, the radius vector and the velocity vector are perpendicular so

'θ' = 90°.

$B= \frac{(4\pi *10^{-7})}{4\pi}\frac{(1.6*10^{-19})(3.9*10^{7}) \vec{r}sin(90)}{(2.1*10^{-5})^2 } = \boxed{1.415 * 10^{-9}T}$

d)
This point is ALONG the velocity vector, so there is no magnetic field produced at this point.

Aka, the radius and velocity vectors are parallel, and since sin(0) = 0, there is no magnetic field at this point.

$\boxed{B = 0 T}$

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2 years ago

2CO + 2NO → 2CO2 + N2 is it balannced

natita [175]

If the same atoms appear on both sides, then it's balanced.

In this reaction, there are 4 Oxygens, 2 Carbons, and 2 Nitrogens on each side. So numerically, it's balanced. But I don't know enough chemistry to say whether the reaction is possible.

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3 years ago

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