Answer:
D. Test a piece of treated iron and a piece of untreated iron under the same conditions.
Explanation:
A controlled experiment is defined as an experiment where the experimenter or the researcher tries to test or experiment his result by changing one variable at a time and keeping the other factors under the same conditions and sees how it effects the result.
The factors which can be changed in an experiment is called its variables.
In the context, testing a piece of treated iron as well as a untreated piece of iron under the same working conditions forms a controlled experiment.
Answer: Kinetic energy is the energy of motion, observable as the movement of an object, particle, or set of particles. Any object in motion is using kinetic energy: a person walking, a thrown baseball, a crumb falling from a table, and a charged particle in an electric field are all examples of kinetic energy at work.
Explanation:
True, all of those careers go in the same category
Speed=Distance/Time. so you need to do distance/speed to get time. 3.84/4.32= .88888888889 seconds to get to his food bowl
Answer:
B.
Explanation:
Given that a student runs up a flight of stairs which info is not needed to calculate the rate of the student is doing work against gravity A the height of the flight of stairs B the length of flight of stairs C the time taken to run up the stairs D the weight of the student
The rate of doing work is known as power.
Power = work done/time
Work done = energy = mgh
Since energy = mgh
Where mg = weight
And h = height
Time = time taken to run up the stairs.
Time, weight mg and height h will be needed while the Length of the flight is therefore not needed.
The correct answer is B.
