Answer: 600 m
Explanation:
Speed 
is defined as the distance traveled 
in a especific time 
:
Where:
is the speed of sound
the time you hear the thunder after you see the flash of lightning
We need to find the distance at which you are from the lightning strike:
Finding :
Finally:
I can confirm, your answer is 800J (Or 800 Joules)!
I just took the test and this was the correct answer :)
You could be counting while running
Answer:
i. rubbing the material against a magnet
ii. placing the material in a magnetic field of opposite polarity
iii. placing the material near a strong magnet
Explanation:
Ferromagnetic materials are majorly metals which can be easily attracted by a magnet. ferromagnetic materials are made up of domains, behaves as minute pieces of magnet. They can be rearranged to align when under the influence of an external magnetic field.
The alignment of the domains in a ferromagnetic material can be caused by either of the following: rubbing the material against a magnet, placing the material in a magnetic field of opposite polarity, placing the material near a strong magnet.
Answer:
160N/m
Explanation:
According to Hooke's law which states that the extension of an elastic material is directly proportional to the applied force provided that the elastic limit is not exceeded. Mathematically,
F = ke where
F is the applied force
k is the spring constant
e is the extension
From the formula k = F/e
Since the body accelerates when the block is released, F = ma according to Newton's second law of motion.
The spring constant k = ma/e where
m is the mass of the block = 0.4kg
a is the acceleration = 8.0m/s²
e is the extension of the spring = 2.0cm = 0.02m
K = 0.4×8/0.02
K = 3.2/0.02
K = 160N/m
The spring constant of the spring is therefore 160N/m
