Answer:
Bicycle
Explanation:
A compound machine is a machine which is a combination of simple machines.
Simple machines are like the pulley, inclined plane or a screw.
Suppose a bicycle is considered, it has more than one simple machine combined together, for it to work. Wheel and axle is one of them and the beam which is pivoted at a fixed hinge is another simple machine in it.
The pedals of the bicycle function as the lever.
Answer:
Potential energy of spring = 24 Joules.
Explanation:
Given the following data;
Spring constant = 85N/m
Extension, e = 0.75m
Mass = 25kg
To find the potential energy of a spring
Potential energy of a spring is given by the formula;
P.E = ½ke²
Substituting into the equation, we have
P.E = ½*85*0.75²
P.E = 42.5 * 0.5625
P.E = 23.91 ≈ 24 Joules
P.E = 24 Joules
Battery based heaters use electric resistance heating, which uses a lot of current (electricity) to create the heat.
Answer: B. If an object's velocity is changing,it's either experiencing acceleration or deceleration.
Acceleration is defined as the rate at which an object changes its velocity. This implies that if an object is changing it's velocity it is experiencing acceleration/ deceleration.
Acceleration is a vector quantity that has both a magnitude and time.
It is represented as
Acceleration= change in velocity/time.
The SI unit for acceleration is m/s^2