Answer:
The distance traveled in 1 year is:
Explanation:
Given
--- speed
--- time
Required
The distance traveled
This is calculated as:

So, we have:

This gives:


-- approximated
Answer:3.51
Explanation:
Given
Coefficient of Friction 
Consider a small element at an angle \theta having an angle of 
Normal Force

Friction 

and 







Answer:
The number of bright fringes per unit width on the screen is,
Explanation:
If d is the separation between slits, D is the distance between the slit and the screen and
is the wavelength of the light. Let x is the number of bright fringes per unit width on the screen is given by :

is the wavelength
n is the order
If n = 1,

So, the the number of bright fringes per unit width on the screen is
. Hence, the correct option is (B).
ANSWER:
3408.81 kg
STEP-BY-STEP EXPLANATION:
Given:
v = 111 m/s
Ek = 21000000 J
We have that the formula for kinetic energy is as follows:

We substitute the values given in the exercise and solve for m (mass)

The mass of the helicopter is 3408.81 kilograms.
Answer: The correct statements are:
- The atoms are very attracted to one another.
- The atoms are held tightly together.
Explanation:
Solid state: In this state, the molecules are closely packed and cannot move freely from one place to another that means no space between them and the intermolecular force of attraction between the molecules are strong.
In solid substance, the particles are very close to each other due to this the intermolecular forces of attraction are strongest.
The key point about solid are:
- The atoms are very attracted to one another.
- The atoms are not moving freely.
- It will not spread out evenly to fill any container.
- The atoms are held tightly together.
- The forces of attraction are strong to bring molecules together.
- The atoms are close and in fixed positions.