Units and Measurements + Motion in a St. Line
What are the dimensions of 'solid angle'?
It is a dimensionless quantity.
Which type of vector has no sense of direction?
A null vector
An illustration for Newton's Third Law of motion.
Any
1hp = _______ W
746
For a rigid rod of length 'l' metres, what will be the moment of inertia?
(1/4) Ml2
What is zero for a body in uniform motion?
Acceleration
What is the relation between the time of maximum height(tm) and the time of flight(Tf)?
Tf = 2 tm
On a levelled road, what force provides the centripetal force required for circular motion?
Frictional Force
What is kWh the unit of?
Power
For a body in uniform rotational motion, what is the velocity of a particle on the axis of rotation?
zero
Mention the three equations of motion for a body in free-fall.
v = -gt
y = – ½gt2
v2 = – 2gy
What is centripetal acceleration in terms of angular velocity ω ?
ac = ω2R
List 3 contact forces in nature.
Friction, viscosity, air resistance, tension, etc
One difference between Conservative and Non-conservative Forces.
Any one
What are the two conditions for the equilibrium of a rigid body?
1. Translational equilibrium
2. Rotational equilibrium
An object moves once in a circular path of radius 3m. What is the relation between distance and displacement for this particle?
Distance>Displacement
What is the angle between î and ĵ?
90o
Driving at this speed on a banked road will cause little wear and tear of the tyres.
vo = (R g tan θ)½
What happens if two equal masses collide with each other in a perfectly elastic manner?
The first mass comes to rest and pushes off the second mass with its initial speed on collision.
When the angular momentum of a rotating body is conserved, as the moment of inertia increases, what quantity decreases?
Angular velocity
5.74 g of a substance occupies 1.2 cm³. Express its density by keeping the significant figures in view.
4.8 g/cm³
The maximum horizontal range of a projectile is 1960m. What is the initial velocity?
138.6 m/s
A bullet of mass 50g moving at 500m/s hits a wooden plank and comes to rest in 0.01s. What is the impulse?
-25Ns
When a spring is subjected to an external force of 20N, it is extended by 5m. What is its spring constant?
A 6kg wheel has a radius of gyration of 0.1m. What is the torque required to increase its acceleration to 5rad/s2?
0.3 Nm