Physics generates fundamental knowledge needed for the future technological advances that will continue to drive the economic engines of the world. Physics contributes to the technological infrastructure and provides trained personnel needed to take advantage of scientific advances and discoveries.
First write down all your known variables:
vi = 25m/s
a = 7.0m/s^2
t = 6.0s
vf = ?
Then choose the kinematic equation that relates all the variables and solve for the unknown variable:
vf = vi + at
vf = (25) + (7.0)(6.0)
vf = 67m/s
The final velocity of the motorcycle is 67m/s.
Answer: C is right
Explanation: Most of the sound waves are reflected back but waves passing opening will speread to all directions outside because of diffraction
Answer:
v = 2 v₀
Explanation:
For this exercise we will use the relationship between work and the change in kinetic energy
W = ΔK
Where the work is of the friction force, which is always opposed to the movement whereby the angle is 180º
W = - fr x
The distance for the first case is
x = 1/4 L
We substitute
-fr ¼ L = ½ m v₀²
fr L = 2 m v₀²
In the second case, the new speed takes the ball the entire distance
x = d
-fr L = ½ m v²
We equal the two equations
2 m v₀² = ½ m v²
v² = 4 v₀²
v = 2 v₀
