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almond37 [142]
4 years ago
12

A truck is moving with a certain uniform velocity. It is accelerated uniformly by 0.75 m/s^2. After 20 seconds , the velocity be

comes 72km/h.Find the initial velocity
Physics
1 answer:
scoundrel [369]4 years ago
5 0

Answer:

Vi = 5 m/s

Explanation:

let (a) acceleration = 0.75 m/s²

(t) time = 20 seconds

Vf = final velocity = 72 km/hr  (convert to m/s to units consistency = 20 m/s)

find Initial velocity (Vi)

       Vf - Vi

a =  -----------

             t

Vi = Vf - (a * t)  = 20 - (0.75 * 20)

Vi = 5 m/s

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A girl launches a toy rocket from the ground. The engine experiences an average thrust of 5.26 N. The mass of the engine plus fu
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Answer: The answer for A is - v = 786.93 m/s

The answer for B is - v = 122.40 m/s

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a) To find the average exhaust speed (v) of the engine we can use the following equation:

F = vΔm

Where:

F: is the thrust by the engine = 5.26 N

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v = F×ΔT/ΔT

b) To calculate the final velocity of the rocket we need to find the acceleration.

The acceleration (a) can be calculated as follows:

a = F/M

In the above equation, m is an average between the mass of the engine plus the rocket case mass and the mass of the engine plus the rocket case minus the fuel mass:

m = (m_{engine} + m_{rocket}) + (m_{engine} + m_{rocket} - m_{fuel})}{2} = {2*m_{engine} + 2*m_{rocket} - m_{fuel}}{2} = 2*25.0 g + 2*63.0 g - 12.7 g}{2} = 81.65 g

Now, the acceleration is:

a = 5.26 N/81.65-t 10^³kg} = 64.42 m*s^²

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1 kg mass = 2.2 pounds
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a) The magnetic field created by a current-carrying wire is proportional to the current:

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