Answer:
Three machines that humans have created are the lever, the wheel, and the axle, and also a pulley. even though there's actually more. A lever is A rigid bar that is free to move around a fixed point, such as a screwdriver. The wheel and axle, everyone should know what that is and what it does, it lifts heavy objects, moves people quickly, and moves parts of a complex machine. Pulleys are used to lift things, pulleys can be used singly or with many pulleys working together in order to transport people or things. They can also be used to provide power from one shaft to another. ... Construction pulleys are used in order to lift and place heavy materials.
Answer:
1)a. It is constant the whole time the ball is in free-fall.
2)b. = 14 m/s
3) e. = 19.6 m/s
Explanation:
1) given that the only force acting on the ball is gravity, gravity acts along the vertical axis. Since no other force acts on the ball then the horizontal velocity will remain constant all through the flight since there is no horizontal force acting on the ball.
2) speed = distance/time
horizontal distance = 56m
Time = 4 seconds
Speed = 56m/4s = 14m/s
3) acceleration due to gravity g = 9.8m/s^2
Initial vertical velocity = u
Final vertical velocity = v = -u
Using the law of motion;
v = u + at
a = acceleration = -g = -9.8m/s^2
t = time of flight = 4
Substituting the values;
-u = u - 4(9.8)
-2u = -4(9.8)
u = -4(9.8)/-2
u = 2(9.8) = 19.6 m/s
Initial vertical velocity = u = 19.6 m/s
Self productive and it depends on how whom is behaving.
Material medium electric waves
I believe that the answer to this would be B
Hope this helped
