Answer:
<em>a. 137.5 m</em>
<em>b. 550 m</em>
Explanation:
<u>Accelerated Motion
</u>
If an object is changing its velocity at a constant rate, it has a uniformly accelerated motion. When the object is moving in one fixed axis, then the sign of the acceleration is negative if the object is braking, and positive if the object is increasing its speed.
The initial speed vo, final speed vt, acceleration a, and distance traveled x are related by the formula
a. The Race Car A has an initial speed of 55 m/s and it's said to stop. We must find at what distance it goes to vf=0. This means that the above formula becomes
Solving for x
The acceleration is , negative because it's against the movement. Thus
b. If the car is going twice as fast (v0=110 m/s), then
Answer:
2 secs; 65 feet
Explanation:
The function guiding the water bottle is given as:
f(x) = -16t² + 64t + 1
The bottle will reach maximum height when velocity, df/dt (velocity is the first derivative of distance) = 0.
Therefore:
df/dt = 0 = -32t + 64
=> 32t = 64
t = 64/32 = 2 seconds
This is the time it will take to reach the maximum height.
To find this height, we insert t = 2 into the function f(x):
f = -16(2)² + 64(2) + 1
f = -(16 * 4) + 128 + 1
f = -64 + 128 + 1
f = 65 ft
Its maximum height is 65 ft.
Answer:
E = 15.7 KJ/mol
Explanation:
The number of vacancies in a metal is given by
n = n₀
They tell us that
n = 5 no
We replace
5 n₀ = n₀ e^{-E/KT}
-E / KT = ln 5
E = KT ln 5
E = 1,381 10⁻²³ 1170 ln 5
E = 2.6 10⁻²⁰ J
To take (J / mol) we multiply between Avogadro's number
E = 2.6 10⁻²⁰ 6.022 10²³
E = 1.57 10⁴ J / mol
E = 15.7 KJ/mol