<span>When temperature is increased,
the rate of dissolving increases. The kinetic energy of the molecules of the
solute and solvent molecules is high thereby increasing their contact. An example
is mixing powdered sugar to the water. When you add water to the sugar, the
dissolving process is slow. However, when you increase the temperature of the
water by boiling it, the sugar dissolves immediately. </span>
3 - b) weight decreases
4 -a) 50 kg as mass is same everywhere
5 - b) 200 dynes
Answer:
Mechanical energy
Explanation:
A car changes chemical energy from fuel into thermal energy and mechanical energy.
Mechanical energy can be defined as the type of energy that is possessed by an object due to its motion or position. Mechanical energy is the sum of potential energy and kinetic energy, that is, the sum of energy in motion and stored energy. Examples of mechanical energy includes driving a car, riding a bicycle, listening to music etc.
Types of mechanical energy
1. Motion energy (kinetic energy)
2. Stored energy(potential energy)
Mechanical energy = Kinetic energy + Potential energy
Cloud Formation<span> Due to Surface Heating. Some </span>clouds<span>form due to the heating of the Earth's surface. First, the </span>Sun<span>heats the ground, which then heats the air. ... This extra water vapor begins to condense out of the air parcel in the form of liquid water droplets.</span>
Answer:

Explanation:
<u>Friction Force</u>
When objects are in contact with other objects or rough surfaces, the friction forces appear when we try to move them with respect to each other. The friction forces always have a direction opposite to the intended motion, i.e. if the object is pushed to the right, the friction force is exerted to the left.
There are two blocks, one of 400 kg on a horizontal surface and other of 100 kg on top of it tied to a vertical wall by a string. If we try to push the first block, it will not move freely, because two friction forces appear: one exerted by the surface and the other exerted by the contact between both blocks. Let's call them Fr1 and Fr2 respectively. The block 2 is attached to the wall by a string, so it won't simply move with the block 1.
Please find the free body diagrams in the figure provided below.
The equilibrium condition for the mass 1 is

The mass m1 is being pushed by the force Fa so that slipping with the mass m2 barely occurs, thus the system is not moving, and a=0. Solving for Fa
![\displaystyle F_a=F_{r1}+F_{r2}.....[1]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20F_a%3DF_%7Br1%7D%2BF_%7Br2%7D.....%5B1%5D)
The mass 2 is tried to be pushed to the right by the friction force Fr2 between them, but the string keeps it fixed in position with the tension T. The equation in the horizontal axis is

The friction forces are computed by


Recall N1 is the reaction of the surface on mass m1 which holds a total mass of m1+m2.
Replacing in [1]

Simplifying

Plugging in the values
![\displaystyle F_{a}=0.25(9.8)[400+2(100)]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20F_%7Ba%7D%3D0.25%289.8%29%5B400%2B2%28100%29%5D)
