A car of mass 940.0 kg accelerates away from an intersection on a horizontal road. When the car speed is 42.5 km/hr (11.8 m/s), the net powe

Question

A car of mass 940.0 kg accelerates away from an intersection on a horizontal road. When the car speed is 42.5 km/hr (11.8 m/s), the net power which the engine supplies is 4300.0 W (in addition to the extra power required to make up for air resistance and friction). Calculate the acceleration of the car at that time.

in progress 0
Diễm Kiều 7 months 2021-07-20T21:54:51+00:00 2 Answers 2 views 0

Answers ( )

    0
    2021-07-20T21:55:58+00:00

    Answer: The acceleration of the car at that time is 0.39 m/s^2

    Explanation:

    Power (P) is given by

    Power (P) = work done (W) / time (t)

    But, work done (W) = force (F) × displacement (d)

    Therefore,

    Power (P) = (F × d) / t

    But, velocity (V) is defined by

    Velocity (V) = displacement (d) / time (t)

    Hence,

    Power (P) = Force (F) × Velocity (V)

    P = F × V

    Where P is power is Watts (W)

    F is force is Newtons (N)

    and V is velocity in meter / second (m/s)

    To calculate the acceleration, we will first determine the Force, F

    From the question,

    P = 4300.0W

    V = 11.8 m/s

    Therefore,

    4300.0 = F × 11.8

    F = 4300.0 ÷ 11.8

    F = 364.407N

    From the formula,

    F = m × a

    Where m is the mass

    a is the acceleration

    and F is force

    Acceleration is given by,

    a = F / m

    From the question,

    m = 940.0 kg

    Hence,

    a = 364.407 / 940.0

    a = 0.39 m/s^2

    0
    2021-07-20T21:56:29+00:00

    Answer:

    0.39 m/s^2

    Explanation:

    Parameters given:

    Mass of car, m = 940 kg

    Speed of car, v = 11.8 m/s

    Power supplied by engine, P = 4300 W

    To get the acceleration, we must define the relationship between Power and velocity.

    Power, P, is given in terms of velocity, v, as:

    P = F * v

    where F = force

    This is because Power is given as:

    P = \frac{E}{t} \\\\\\P = \frac{F*d}{t} \\\\\\=> P = F * v

    (where E = energy. t = time taken, d = distance moved)

    Force, F, is given as:

    F = m*a

    Therefore, Power will be:

    P = m * a * v

    Acceleration, a, will then be:

    a = \frac{P}{m*v}

    a = \frac{4300}{940 * 118} \\\\\\a = 0.39 m/s^2

    The acceleration of the car at that time is 0.39 m/s^2

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )