5. If the momentum of a body is increased by 100% then the percentage increase in kinetic

A car moves at speed v across a bridge made in the shape of a circular arc of radius r. (a) Find an expression for the normal fo

inna [77]

Answer:

(a) FN = m (g - $\frac{v^{2} }{r}$ )

(b) vmin = 17.146 m/s

Explanation:

The radius of the arc is

r = 30m

The normal force acting on the car form the highest point is

FN = m (g - $\frac{v^{2} }{r}$ )

If the normal force become 0 we have

m (g - $\frac{v^{2} }{r}$ ) = 0

or

g - $\frac{v^{2} }{r}$ = 0

This way, when FN = 0, then v = vmin, so

g - $\frac{vmin^{2} }{r}$ = 0

vmin = $\sqrt[.]{g*r}$ = $\sqrt[.]{9.8 m/s^{2} * 30m } = 17.146 m/s$

4 0

3 years ago

6. An excited dog runs full-speed toward his owner who has just returned home from

mixas84 [53]

Answer:

v = 8.65 m/s

Explanation:

Given that,

Distance covered by the doge, d = 45 m

Time taken, t = 5.2 s

We need to find its average speed. The total distance covered divided by the total time taken is called the average speed of an object. So,

$v=\dfrac{45\ m}{5.2\ s}\\\\=8.65\ m/s$

So, the average speed is 8.65 m/s.

4 0

3 years ago

At takeoff, an aircraft travels at 62 m/s, so that the air speed relative to the bottom of the wing is 62 m/s. Given the sea lev

olganol [36]

Answer:

the aircraft must travel at a speed of 73.4 m/s in order to create the ideal lift.

Explanation:

We will use Bernoulli's theorem in order to determine the pressure lift:

ΔP = 1/2 (ρ)(v₂² - v₁²)

the generated pressure lift is ΔP = 1000 N/m²

Therefore,

1000 = 1/2(ρ)(v₂² - v₁²)

v₂² - v₁² = 2000 / ρ

v₂² = (2000 N/m² / 1.29 kg/m³) + (62 m/s)²

v₂ = √[ (2000 N/m² / 1.29 kg/m³) + (62 m/s)² ]

v₂ = 73.4 m/s

Therefore, the aircraft must travel at a speed of 73.4 m/s in order to create the ideal lift.

5 0

3 years ago

La luz roja visible tiene una longitud de onda de 680 nanómetros (6,8 x 10-7 m). La velocidad de la luz es de 3.0 x108 m / s. ¿C

Lina20 [59]

Answer:

Frequency, $f=4.41\times 10^{14}\ Hz$

Explanation:

Visible red light has a wavelength of 680 nanometers (6.8 x 10⁻⁷ m). The speed of light is 3.0 x 10 ⁸ m / s. What is the frequency of visible red light?

It is given that,

Wavelength of a visible red light is, $\lambda=6.8\times 10^{-7}\ m$

Speed of light is, $c=3\times 10^8\ m/s$

We need to find the frequency of visible red light. It can be calculated using below relation.

$c=f\lambda\\\\f=\dfrac{c}{\lambda}\\\\f=\dfrac{3\times 10^8}{6.8\times 10^{-7}}\\\\f=4.41\times 10^{14}\ Hz$

So, the frequency of visible red light is $4.41\times 10^{14}\ Hz$ .

3 0

3 years ago

How many moons does Venus have?

Gennadij [26K]

The answer is no moons at all. That's right, Venus (and the planet Mercury) are the only two planets that don't havea single natural moon orbiting them. Figuring out why is one question keeping astronomers busy as they study the Solar System.

4 0

3 years ago

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