Answer:
Closed system, because the speed of the car is as expected in the case where an object has uniform acceleration for a time t
Explanation:
Here in the question it is mentioned that a toy car has an initial acceleration of 2m/s² across a horizontal surface so we can say that it is acted upon by an external force
Assuming that the acceleration is constant and the reason for this assumption is there at the last
The major difference between an open system and closed system is in case of open system there will be transfer of matter and in case of closed system there will be no change in matter of the system
If acceleration is constant in case of closed system we can expect the speed of the car after a time t by using the formula
s = u×t + 0·5×a×t²
where s is the distance travelled
t is the time taken to travel that distance
u is the initial velocity
a is the acceleration of that system
But in case of open system as there will be a change of mass there will be a change in velocity of the system so in this case we cannot expect the speed of the car after a time t
And if the acceleration is not constant then we cannot say that the toy car is an open system or closed system, that is why we are assuming that the acceleration of the toy car is constant
Your answer should be D
let me know if I got it wrong
Hope this helped!
Answer:
mantle convection is the very slow creeping motion of earths solid silicate mantle caused by convection currents carrying heat from the interior to the planet's surface.
Answer:
A. Vx = 3.63 m/s
B. Vy = -45.73 m/s
C. |V| = 45.87 m/s
D. θ = -85.46°
Explanation:
Given that position, r, is given as:
r = 3.63tˆi − 5.73t^2ˆj + 8.16ˆk
Velocity is the derivative of position, r:
V = dr/dt = 3.63 - 11.46t^j
A. x component of velocity, Vx = 3.63 m/s
B. y component of velocity, Vy = -11.46t
t = 3.99 secs,
Vy = - 11.46 * 3.99 = -45.73 m/s
C. Magnitude of velocity, |V| = √[(-45.73)² + 3.63²]
|V| = √(2091.2329 + 13.1769)
|V| = √(2104.4098)
|V| = 45.87 m/s
D. Angle of the velocity relative to the x axis, θ is given as:
tanθ = Vy/Vx
tanθ = -45.73/3.63
tanθ = -12.6
θ = -85.46°
When an object in simple harmonic motion is at its maximum displacement, its <u>acceleration</u> is also at a maximum.
<u><em>Reason</em></u><em>: The speed is zero when the simple harmonic motion is at its maximum displacement, however, the acceleration is the rate of change of velocity. The velocity reverses the direction at that point therefore its rate of change is maximum at that moment. thus the acceleration is at its maximum at this point</em>
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Hope that helps!
