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Vera_Pavlovna [14]

2 years ago

14

A truck collides with a car on horizontal ground. At one moment during the collision, the magnitude of the acceleration of the t

ruck is 12.7 m/s^2. The mass of the truck is 2490 kg and the mass of the car is 890 kg. Assume that the only horizontal forces on the vehicles during the collision are the forces they exert on one another.
Required:
What is the acceleration of the car at the same moment?

1 answer:

Mice21 [21]2 years ago

3 0

Answer:

The magnitude of the acceleration of the car is 35.53 m/s²

Explanation:

Given;

acceleration of the truck, $a_t$ = 12.7 m/s²

mass of the truck, $m_t$ = 2490 kg

mass of the car, $m_c$ = 890 kg

let the acceleration of the car at the moment they collided = $a_c$

Apply Newton's third law of motion;

Magnitude of force exerted by the truck = Magnitude of force exerted by the car.

The force exerted by the car occurs in the opposite direction.

$F_c = -F_t\\\\m_ca_c = -m_t a_t\\\\a_c =- \frac{m_ta_t}{m_c} \\\\a_c = -\frac{2490 \times 12.7}{890} \\\\a_c = - 35.53 \ m/s^2$

Therefore, the magnitude of the acceleration of the car is 35.53 m/s²

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