Answer:
Iron
Explanation:
Steel is the purest form of iron with a little amount of carbon mixed in it. As we all know that iron is attracted towards magnet therefore we can say that steel can also be attracted towards magnet.
Answer : The frequency decreases by a factor of 2.
Explanation :
Given that the wave travels at a constant speed. The speed of the wave is given as :
Where
υ is the frequency of the wave
and λ is the wavelength of the wave.
In this case, the speed is constant. So, the relation between the frequency and the wavelength is inverse.
If the wavelength increases by a factor of 2, its frequency will decrease by a factor of 2.
Hence, the correct option is (A) " The frequency decreases by a factor of 2 ".
b. False
Answer:
The apparent weight of a freely falling body is zero. When a body falls freely, it is falling with an acceleration =g. Thus the entire gravitational force acting on it is utilized in accelerating it and hence its weight is not felt.
Gravity
Pressure
Nuclear explosions.
B. low enough to combine
C. low enough to overcome
D. equal to
E. great enough to overcome
Answer: E. great enough to overcome.
Explanation: The three phases of the substances are solid, liquid and gas.
When a substance is heated, that is the molecules gain kinetic energy as kinetic energy is directly proportional to temperature.
The phase change will take place only when kinetic energy will be greater than the inter molecular forces as the molecules have to move in more random motion.
For example: Solid with high inter molecular forces are heated to convert it into liquid state only when kinetic energy will overcome the inter molecular forces of attraction.