Air resistance - class-XII
Description: air resistance | |
Number of Questions: 25 | |
Created by: Nitesh Divan | |
Tags: force and pressure physics friction mechanics dynamics - explaining motion force |
Fill in the blanks
Dynamic Fluid friction is _______ the sliding friction of solids.
The frictional force exerted by fluids is called:
Boats and aeroplanes are ................. so as to reduce fluid friction.fill in the blank.
Fluid friction is exerted by _____ .
Fluid friction depends on ______
What measures are taken to reduce fluid friction in aeroplanes?
To move at same speed, a car with flat face and another with streamlined body, will require different amount of force from the engine. The engine of the streamline bodied car will:
While the arrow moves towards its target, the force acting on it are due to gravity and due to ____ of air.
Driving a car on a highway with windows open reduce the speed. This is due to:
________________ is a force that resists the movement of a solid object through a fluid.
What is drag ?
If we drop a cup of water on a plate and a cup of oil on another plate, water is seen to spread faster along diameter. This is an example related to:
The deeper we go inside a flowing river, fluid friction:
Which of the following statements indicates advantage of fluid friction?
Hailstones falling from atmosphere relates to:
Aeroplanes are streamlined to reduce friction.
Aeroplanes are streamlined to reduce:
A spherical body of radius R consists of a fluid of constant density and is in equilibrium under its own gravity. If$ P(r)$ is the pressure at $r(r < R)$, then the correct option(s) is(are)?
Mr. Verma (50 kg) and Mr. mathur (60 kg) are sitting at the two extreames of 4 m long boat (40 kg) standing still in water. to discuss a mechanics problem, they come the middle of the boat . neglecting friction with water, how far does the boat move in the water during the process?
Smooth surface produces ----- friction than a rough surface.
The arrow with a pointed tip can move faster in air than that of with a blunt tip.
State whether the given statement is true or false:
A man of mass $m$ walks from end $A$ to the other end $B$ of a boat of mass $M$ and length $l$. The coefficient of friction between the man and the boat is $ \mu $ and neglect any resistive force between the boat and the water.