Here when an object is placed on the level floor then in that case there are two forces on the object
1). Weight of object downwards (mg)
2). Normal force due to floor which will counterbalance the weight (N)
so when no force is applied on the box at that time normal force is counter balanced by weight.
Now here it is given that A person tried to lift the box upwards
So now there are two forces on the box
1). Applied force of person
2). Normal force due to ground
So now these two forces will counter balance the weight of the crate
So we can write an equation for force balance like

given that

here
m = 30 kg and
g = acceleration due to gravity = 10 m/s^2

now from above equation


So force applied by the person must be 150 N
Question no. 1. Compare the planets Mars and Saturn. Describe how their common characteristics are similar:
Answer: Our solar system is located in the outer spiral arm of the milky way galaxy. our solar system has one sun and nine revolving planets and . namely
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
- Pluto (small planet usually refer as dwarf)
Each star has its on moon/moons and has its own characteristics i.e , planet must be a celestial body , must have orbit around sun, have enough mass for self gravity, big enough to have gravity that clear its path from other same size object close to its orbit around sun.
Mars is the fourth from the sun and sixth is the Saturn from the sun in our solar system.
<u>Common in Characteristics of Mars and Saturn:</u>
- Mars and Saturn both have celestial body.
- Mars and Saturn both have enough mass for the gravity to get rid of rigid body forces.
- Mars and Saturn both revolve around the sun in their own orbits.
- Mars is the second smallest in the solar system while Saturn is second largest in the solar system.
- Mars and Saturn both have their own moons. Mars has two while Saturn has 83 moons
- Mars and Neptune both do not support life.
Question no. 2. Compare the planets Earth and Neptune. Describe how are they different from each other
Answer:
Earth our home planet is the third from the sun and Neptune on the other hand is the eighth from the sun in the solar system.
<u>Common differences between Earth and Neptune</u>
- Earth is the terrestrial planet while Neptune (Ice giant) is the Jovian planet.
- Earth has no ring around it, Neptune has ring around it.
- Earth is closer to the sun and Neptune is far distant from the sun.
- Earth consists of rocks and metals on the other hand Neptune contain gases
- Earth is smaller than the Neptune in the solar system.
- Earth rotates slower and Neptune rotates faster.
Answer:

Explanation:
We can use the following SUVAT equation to solve the problem:

where
v = 0 is the final velocity of the car
u = 24 m/s is the initial velocity
a is the acceleration
d = 196 m is the displacement of the car before coming to a stop
Solving the equation for a, we find the acceleration:

A magnet is a substance which attracts or repels another substance. In a magnet, the atoms are aligned in a particular direction in domains. A magnet has two poles: North pole and South pole. The domains are oppositely aligned in unlike poles. Like poles repel each other where as unlike poles attract each other. Hence, when we bring like poles closer, repulsion would be experienced. In case of unlike poles, they would stick together.