Daily NEET MCQ- September 6, 2022 - NEET MCQ

ABomb calorimeter works at constant volume, so it is isochoric in nature. Here, the heat energy that’s measured is only the internal energy. The work done is zero because of no change in volume.

The latent heat of vaporization of water is 2260 KJ/Kg. The heat that is required to convert water at 373 k to steam is given by Q = mL, where m = mass of the water and L = latent heat vaporization of water; heat energy required = 1 kg x 2260 KJ/Kg = 2260 KJ.

We know that ΔH = ΔU + PΔV; ΔH is the enthalpy, ΔU is the internal energy, ΔV is the change in volume and P is the pressure. So by substituting the enthalpy, internal energy during a process and change in volume as 500 units, 400 units and 2 units, we get pressure as 50 units.

Bernoulli’s equation can be used for non-viscous, incompressible and steady laminar flow.

We should apply Bernoulli theorem between the top surface of water and the hole. The area of hole is very small when compared to the area of the tank. So, 1/2ρv² at the top surface of the tank can be neglected.
P₀ + F/AP + ρgh = P₀ + 1/2ρv²
∴ 1000/10 + 1000*10*0.1 = 0.5*1000 *v²
∴ v = 1.48m/s

At the contact surface of two bodies (here, fluid layers) molecular bonds are formed. When there is relative motion between them these bonds try to oppose it. This is how friction works. Therefore we can say it is an electromagnetic force as molecular bonds are considered to be electromagnetic forces.

In the case of liquids when temperature increases, viscosity decreases because it is the result of molecular bonds (electromagnetic forces) between particles which weaken due to random motion brought about by increase in temperature. In the case of gases, the molecules vibrate more randomly, leading to more obstruction in the path of bodies trying to move through it. And we interpret this increased obstruction as increased viscosity of the gas.

Resistance force by a fluid on a body = 6πηrv, where η is coefficient of viscosity, r is radius of body & v is its velocity. This doesn’t depend on density.
Another way to think of this is to imagine a hollow and solid sphere of the same radius falling through air at the same speed. The resistance offered by air will be the same on both as they have the same surface area exposed and are moving at the same speed.

The reaction center in the light-harvesting complex is formed by a single “chlorophyll a” molecule. This chlorophyll a molecule has the capability to absorb different wavelengths of light energy. It is mainly known for the process called photoionization of chlorophyll.

Electron transport is not related to light reaction. It is because light reaction is mainly based on photochemical processes like light absorption, water splitting, the formation of ATP and NADPH, etc. where electron transport is not included.