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3 years ago

6

If a car is moving on a highway at 70 km/hr, going South and then turns to travel 70 km/hr East. What happens to the cars speed

and velocity?
(A)Speed - changing, Velocity - constant

(B)Speed - constant, Velocity - changing

(C)Speed - constant, Velocity - constant

(D)Speed - changing, Velocity - changing

1 answer:

frozen [14]3 years ago

6 0

Answer:

(B)Speed - constant, Velocity - changing

Explanation:

The magnitude of the velocity ( speed ) has not changed as car is traveling constantly at 70 km/h. But we know the velocity is also having a direction component, and the car which was traveling South is now traveling East. As direction is changed, velocity is changed but as magnitude of velocity has not changed, the speed remain unchanged.

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omeli [17]

To solve this problem we will apply the Newtonian concept of gravitational acceleration produced by a planet. This relationship is given by:

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Where,

G = Gravitational Universal Constant

M = Mass of Earth

r = Radius

The values given are based on the constants of the earth, so they can be expressed as

$M_p = \frac{1}{100} M_e$

$r_p = \frac{1}{4} r_e$

The relationship of gravity would then be given:

$g_e = \frac{GM_e}{r_e^2}$

The relationship with the new planet, from the gravity of the earth would be given

$g_p = \frac{GM_p}{r_p^2}$

$g_p = \frac{G(1/100)M_e}{(1/4 r_e)^2}$

$g_p = \frac{GM_e 16}{100 r_e^2}$

$g_p = 0.16 \frac{GM_e}{r_e^2}$

$g_p = 0.16g_e$

The relationship with the weight of the earth would be given as:

$W_e = m*g_e = 600N$

$W_p = m*g_p = m(0.16g_p)$

$W_p = (m*g_p)(0.16)$

$W_p = 600*0.16$

$W_p = 96N$

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I need help with question 26<br>this is from my physics textbook

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4 years ago

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Elis [28]

Answer:

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Explanation:

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Torque is applied for duration , $\Delta t=79ms=0.079s$

(a)

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lesya [120]

Answer:

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zloy xaker [14]

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