This problem can be solved using a kinematic equation. For this case, the following equation is useful:
v_final = v_initial + at
where,
v_final = final velocity of the nail
v_initial = initial velocity of the nail
a = acceleration due to gravity = 9.8 m/s^2
t = time
First, we determine the time it takes for the nail to hit the ground. We know that the initial velocity is 0 m/s since the nail was only dropped. It has a final velocity of 26 m/s. We substitute these values to the equation and solve for t:
26 = 0 + 9.8*t
t = 26/9.8 = 2.6531 s
The problem asks the velocity of the nail at t = 1 second. We then subtract 1 second from the total time 2.6531 with v_final as unknown.
v_final = 0 + 9.8(2.6531-1) = 16.2004 m/s.
Thus, the nail was traveling at a speed of 16. 2004 m/s, 1 second before it hit the ground.
Answer:
The runner's acceleration as she sped up to the finish line is 0.95m/s²
Explanation:
Acceleration is the change in velocity of a body with respect to time. It is expressed as;
Acceleration = change in velocity/time
Change in velocity = final velocity - initial velocity
Acceleration = final velocity - initial velocity / time
Given initial speed = 8.0m/s
Final speed = 9.9m/s
Time taken = 2.0s
Acceleration = 9.9-8.0 / 2.0
Acceleration = 1.9/2
Acceleration = 0.95m/s²
Answer:
The temperature of the water increases because the nuclear reactor heats it producing steam
Explanation:
The nuclear power plants are usually defined as those thermal plants where the nuclear reactors are used in order to generate heat that eventually leads to the rotating of the turbines and produces electricity. Here the nuclear reactor heats the water, and it increases above a temperature of 100°C, where this heat energy plays a key role in the entire process. It is an efficient method as it does not lead to the emission of any green house gases that are harmful to the environment.
Answer:
a)
, b)
, c) 
Explanation:
a) The initial potential energy is:


b) The efficiency of the bounce is:


c) The final speed of Danielle right before reaching the bottom of the hill is determined from the Principle of Energy Conservation:





Answer:
F = 0.768 i ^ - 0.576 j ^ + 0.24 k ^
the correct answer is "b"
Explanation:
The magnetic force is
F = i l x B
The bold are vectors, in this case they give us the direction of the current and the magnetic field, for which we can solve as a determinant
![F = i \left[\begin{array}{ccc}x&y&z\\3&4&0\\0&5&12\end{array}\right]](https://tex.z-dn.net/?f=F%20%3D%20i%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%26y%26z%5C%5C3%264%260%5C%5C0%265%2612%5Cend%7Barray%7D%5Cright%5D)
resolver
F = i ^ (4 12 - 0) + j ^ (0- 3 12) + k ^ (3 5 - 0)
F = i (48 i ^ - 36 j ^ + 15 k⁾
in this case i is the value of the current flowing through the cable
i = 16 mA = 0.016 A
F = 0.768 i ^ - 0.576 j ^ + 0.24 k ^
When reviewing the different answers, the correct answer is "b"