Answer:
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Answer:
Acceleration is percieved, not constant velocity.
Explanation:
You are most aware when the vehicle is accelerating. At constant velocity you would not be aware of the motion. Only if the system is accelerated the dynamics must be solved considering a pseudo-force (of inertial origin) acting.
It's because of this that:
(A) False. The acceleration can be detected from the inside of a closed car.
(B) False. You would be aware of the motion, but not because humans can sense speed but acceleration.
(C) False. Constant velocity cannot be felt in a closed car.
(D) False. Again, you can't feel constant speed.
<span>First of all, the maximum speed occurs when the object passes through the
equilibrium position
The kinetic energy when the object has this max speed is
K= 1/2 * mass * (1.25 m/s)^2
The potential energy in the spring when the speed is equal to zero
U= 1/2 * k * xmax^2
The maximun force of the spring is
mass*acceleration = k*xmax
m * 6.89 m/s2 = k * xmax
xmax = 6.89* m / k
0.5 * m * 1.56 = 0.5 * k * xmax^2
</span>m * 1.56 = k * (<span>6.89* m / k )^2 </span>
<span>
1.56 m = 47.47 m^2 / k
m/k = 0.032862
period = 2 *pi*sqrt[m/k]
= 2 pi </span><span>sqrt [ </span><span>0.032862]
= 1.139 s
A fourth of the period elapses between the instants of max acceleration and maximum speed
= 1/4* period
= 1/4 * </span><span><span>1.139 s </span>
= 0.284s </span>
Cleavage<span> is the tendency of a </span>mineral<span> to break along smooth planes parallel to zones of weak bonding. Fracture is the tendency of a </span>mineral<span> to break along curved surfaces without a definite shape. These </span>minerals<span> do not have planes of weakness and break irregularly.</span>
