Frictional force and Applied force has same “magnitude” and “opposite” direction.
Option: B
<u>Explanation</u>:
When a book is moved horizontally by applying “force” on the book, the frictional force is opposed to the book by the table. Here, this “frictional force” is opposing the book has the same force what we applied on the book but this frictional force and the applied force are opposite in direction. Always the “frictional force” is opposite to the “applied force” which stops the object to move. For example, if a force applied leftward to the object the frictional force is acted on the right side of the object.
When two objects are in contact they experience a "frictional force". This "frictional force" acts opposite to the force applied on to move the object.
Formula for "frictional force" is 
Where, 
is coefficient of friction and N is normal force.
Answer:
v = 3.00 x 10⁸ m/s
Explanation:
given,
speed of light in vacuum = 299,792,458 m/s
speed of light in scientific notation to three significant figures
v = 2.99792458 x 10⁸ m/s
by rounding off the speed to three significant figure.
v = 3.00 x 10⁸ m/s
On the fourth place the value is greater than 5 so, on the third place 1 will be added.
now, the speed with three significant figure comes out to be
v = 3.00 x 10⁸ m/s
Answer:
Same frequency, shorter wavelength
Explanation:
The speed of a wave is given by
where,
f = Frequency
= Wavelength
It can be seen that the wavelength is directly proportional to the velocity.
Here the frequency of the sound does not change.
But the velocity of the sound in air is slower.
Hence, the frequency remains same and the wavelength shortens.
The steel traps the heat more making it hotter,you put this twice by the way.
Their atomic number?? (easy guess)
