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3 years ago

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A car moves at a constant speed of 90km/h from a starting point. Another car moves at 70km/h after 2hours from the same starting

point. if both cars moves in the same direction, after how many hours will the distance between the first car and the second car to be 40 km.

1 answer:

emmainna [20.7K]3 years ago

5 0

Answer:

400

Explanation:

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According to the Guinness Book of World Records, the longest home run ever measured was hit by Roy "Dizzy" Carlyle in a minor-le

Alina [70]

Range of a projectile motion is given by
R = v cos θ / g (v sin θ + sqrt(v^2 sin^2 θ + 2gy_0)); where R = 188m, θ = 41°, g = 9.8m/s^2, y_0 = 0.9

188 = v cos 41° / 9.8 (v sin 41° + sqrt(v^2 sin^2 41° + 2 x 9.8 x 0.9)) = 0.07701(0.6561v + sqrt(0.4304 v^2 + 17.64)) = 0.05053v + 0.07701sqrt(0.4304v^2 + 17.64)
0.07701sqrt(0.4304v^2 + 17.64) = 188 - 0.05053v
0.005931(0.4304v^2 + 17.64) = 35344 - 19v + 0.002553v^2
0.002553v^2 + 0.1046 = 35344 - 19v + 0.002553v^2
19v = 35344 - 0.1046 = 35343.8954
v = 35343.8954/19 = 1860 m/s

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3 years ago

Chlorine contains 17 protons and 19 neutrons, and 18 electrons. What is the net charge of the ion?

Ymorist [56]

Answer:

Net Charge is -1.6 x 10 (to the negative 19th power) C. l

Explanation:

4 0

3 years ago

A ball is kicked horizontally from a 60 meter tall cliff at 10 m/s. How far from

o-na [289]

Hi there!

We can begin by deriving the equation for how long the ball takes to reach the bottom of the cliff.

$\large\boxed{\Delta d = v_it+ \frac{1}{2}at^2}}$

There is NO initial vertical velocity, so:

$\large\boxed{\Delta d= \frac{1}{2}at^2}}$

Rearrange to solve for time:

$2\Delta d = at^2\\\\t = \sqrt{\frac{2\Delta d}{g}}$

Plug in the given height and acceleration due to gravity (g ≈ 9.8 m/s²)

$t = \sqrt{\frac{2(60)}{(9.8)}} = 3.5 s$

Now, use the following for finding the HORIZONTAL distance using its horizontal velocity:

$\large\boxed{d_x = vt}\\\\d_x = 10(3.5) = \karge\boxed{35 m}$

6 0

3 years ago

A spring with spring constant 33N/m is attached to the ceiling, and a 4.8-cm-diameter, 1.5kg metal cylinder is attached to its l

mylen [45]

Answer:

0.423m

Explanation:

Conversion to metric unit

d = 4.8 cm = 0.048m

Let water density be $\who_w = 1000 kg/m^3$

Let gravitational acceleration g = 9.8 m/s2

Let x (m) be the length that the spring is stretched in equilibrium, x is also the length of the cylinder that is submerged in water since originally at a non-stretching position, the cylinder barely touches the water surface.

Now that the system is in equilibrium, the spring force and buoyancy force must equal to the gravity force of the cylinder. We have the following force equation:

$F_s + F_b = W$

Where $F_s = kx$ N is the spring force, $F_b = W_w = m_wg = \rho_w V_s g$ is the buoyancy force, which equals to the weight $W_w$ of the water displaced by the submerged portion of the cylinder, which is the product of water density $\rho_w$ , submerged volume $V_s$ and gravitational constant g. W = mg is the weight of the metal cylinder.

$kx + \rho_w V_s g = mg$

The submerged volume would be the product of cross-section area and the submerged length x

$V_s = Ax = \pi(d/2)^2x$

Plug that into our force equation and we have

$kx + \rho_w \pi(d/2)^2x g = mg$

$x(k + \rho_w g \pi d^2/4) = mg$

$x = \frac{m}{(k/g) + (\rho_w\pi d^2/4)} = \frac{1.5}{(33/9.8) + (100*\pi * 0.048^2/4)} = 0.423 m$

6 0

3 years ago

The Millennium Falcon was constructed 43.6 m long. a) How fast is it traveling past Luke when he measures its length to be 30.1

Zinaida [17]

Answer:

a)0.5564c

b)43.6 m

Explanation:

Given proper length of falcrum L₀= 43.6 m

improper length L=30.1 m (when viewed from moving frame)

we know that $L=L_{0}\sqrt{1-\frac{v^2}{c^2}}$

$30.1=43.6\sqrt{1-\frac{v^2}{c^2}$

⇒ $\{1-\frac{v^2}{c^2}}$ = $\frac{30.1}{43.6}$

${1-\frac{v^2}{c^2}}=0.6904$

$\frac{v^2}{c^2}=0.3096$

$v^{2}=3096c^{2}$

v=0.5564c

this is the required speed of falcon when it passes luke

b). Since Han solo is on the Falcon its reference frame will be falcon itself hence there wont be any change in the length of Falcon that its length will be

43.6 m

8 0

3 years ago