Answer:
180,000
Explanation:
Frequency is a quantity that is measured in Hertz [Hz] and it represents the number of rotations per second.
A motor with a frequency of 50 Hz will rotate 50 times per second.
Since we don't want to know how many times it rotates per second, but per hour. The first step is to find how many seconds there are in an hour and then multiply that amount by 50.
Seconds in an hour:
there are 60 seconds per minute, and 60 minutes per hour, thus there are
60*60 = <u>3,600 seconds in an hour</u>
We know that the motor will rotate 50 times per second so to find the number of rotations in 1 hour = 3,600 seconds we multiply:
50*3,600 = 180,000 rotations
It stops accelerating when the air resistance is equal to its weight.
That's (m•g)
= (2 kg) • (9.8 m/s^2)
= 19.6 newtons
The boat is moving at 22 m/s while the man is moving at 23.1 m/s.
That means the man, relative to the boat, is moving at 23.1-22 = 1.1 m/s.
v =d/t, so t = d/v --> t = 3/1.1 = 2.7 s
Answer:
Limewater can be used to detect carbon dioxide. If carbon dioxide is bubbled through limewater then it turns from clear to cloudy/milky in colour. This is why limewater used in a simple respirometer can show that more carbon dioxide is present in exhaled air compared to inhaled air.
Explanation:
The answer is: Expressive vocabulary
Expressive vocabulary refers to the combination of all the words that a person has acquire throughout his/her life and can be used in various type of situations.
This would include all words in the child vocabulary, starting from the child's written language, spoken language or even the child's manually signed words.