Answer: 
Explanation:
Given
mass of laptop m=2 kg
The velocity of car u=8 m/s
The coefficient of static friction is 
The coefficient of kinetic friction is 
As the car is moving, so the coefficient of kinetic friction comes into play
deceleration offered by friction 
Using the equation of motion 
insert the values

Answer:

Explanation:
For light passing through a single slit, the position of the nth-minimum from the central bright fringe in the diffraction pattern is given by

where
is the wavelength
D is the distance of the screen from the slit
d is the width of the slit
In this problem, we have
is the wavelength of the red light
D = 14 m is the distance of the screen from the doorway
d = 1.0 m is the width of the doorway
Substituting n=1 into the equation, we find the distance between the central bright fringe and the first-order dark fringe (the first minimum):

Answer:
It corresponds to a distance of 100 parsecs away from Earth.
Explanation:
The angle due to the change in position of a nearby object against the background stars it is known as parallax.
It is defined in a analytic way as it follows:

Where d is the distance to the star.
(1)
Equation (1) can be rewritten in terms of d:
(2)
Equation (2) represents the distance in a unit known as parsec (pc).
The parallax angle can be used to find out the distance by means of triangulation. Making a triangle between the nearby star, the Sun and the Earth (as is shown in the image below), knowing that the distance between the Earth and the Sun (150000000 Km), is defined as 1 astronomical unit (1AU).
For the case of (
):


Hence, it corresponds to a distance of 100 parsecs away from Earth.
<em>Summary:</em>
Notice how a small parallax angle means that the object is farther away.
Key terms:
Parsec: Parallax of arc second
Answer:
Distance: 75 km
Displacement: 45 km
Explanation:
- Distance is a scalar quantity that refers to the total space covered by an object. It is calculated as the sum of the distances covered in each motion, regardless of their direction. therefore in this case:
distance = 60 km + 15 km = 75 km
- Displacement is a vector quantity whose magnitude is equal to the difference between the final point and the starting point of the motion, so it also takes into account the direction of each motion. In this case, the truck moves 60 km east, and then 15 km west: if we call '0' the starting point, the final point will be then

And so the displacement is
