When a bus starts moving suddenly the part of passengers body in contact goes forward but the upper portion of his body remain at rest as per the rule this is the reason why the passenger fall back
Tuesday, 28 April 2020
when a bullet is fired it exerts a pressure backward give reason
According to the third law of motion every action has opposite and equal reaction and both action and reaction work on different bodies when a bullet is fired out it exerts action force on the gun backward. This is the reason a man handling the gun is pushed backward
why do you fall in the forward direction when a moving bus brakes to a stop and Falls backwards when it accelerates from rest
When a moving vehicle carries a passenger both the vehicle and the passenger move with the same speed in the same direction when the vehicle stops suddenly the portion of assigner's body that remains in contact comes to rest but the upper part of the body wants to remain in the previous condition and hence it bends forward
explain why is is it difficult for a Fireman to hold a hose which ejects large amount of water at a high velocity
The water rushing out a pipe exerts a backward pressure. Since the velocity of water rushing through pipe remains very fast the backward pressure on the pipe too is very fast. As such it is very difficult for a Fireman to hold the pipe
why is it it advised to tie any luggage kept on the roof of a bus with a rope
The velocity of Air on the roof of a bus is felt very high. The luggage placed on the roof of a bus moves as fast as the bus when if fast moving bus change its direction the luggage placed over the roof may be thrown away due to its inertia. Hence the luggage is tightly bound on the roof to protect it against falling away
in cricket a fielder gradually pulls his hands backward while taking a catch why
The fielder tries to spend more time to reduce the velocity of the ball. Thus the impact of fast ball on hand is reduced. In the body is checked suddenly the rate of change of momentum of the ball may be Tu Hai which can couch injury e in the hands of a fielder
Monday, 27 April 2020
if action is always equal to the reaction explain how horses can pull a cart
Leg of horse imposed pressure on ground at certain angle the Earth surface also impose similar force on the Leg of the horse in opposite direction the pressure imposed by Earth had two components vertical component and horizontal component the vertical component balance the weight of the horse and the cart the card is pulled forward due to origin till component
Two trucks han moving on a road with equal velocity one of the two who is entity and the other full of load which truck will need more force to stop
The loaded truck. Because the inertia of loaded truck will be more than the same of the empty truck
explain why why some of the leaves may gate detached from a tree if we vigorously sake its branch
Leaves attached to some branch of a tree remain at rest due to inertia of rest. When a branch is shaken vigorously the branch goes into motion due to the external force since leaves wish to remain at rest due to inertia of waste they fall down under gravitational force after being detached
what happens when you exert a pressure on the wet cloth clarify your observation
In this case the cloth go into motion and water droplets fall down due to inertia of rest
when a carpet is beaten with stick dust comes out of it explain
when a carpet is beaten by a stick it becomes mobile. On the other hand dust particles remains in the collection of the rest due to inertia of rest. Thus on beating they go away from carpet
an object experiences a net zero external unbalanced force. it is possible for the object to be travelling with a non-zero velocity? if yes state the condition that must be placed on the magnitude and direction of the velocity. if no provide a reason
It has two States :-
- The object is in the state of raised the answer of the question is no. Because an object remains in its initial state only in absence of unbalanced force as per Newton's first law of motion.
- If resultant of all the force acting on an object is zero the object will move with its initial velocity and the answer in this condition will be yes.
write impacts of a force
following are the impact of force :-
- It Change speed of object.
- It change the direction of the motion of object.
- It change the shape of an object.
what is interaction
the process of impacting two objects by imposing courses on each other is called as interaction
write the law of conversation of momentum
The addition of momentum of two quantities remains equal before and after their collision. It means the total momentum of two objects remains unchanged and conserved in the process of their collision. Collision is an event in which two or more bodies exert forces on each other for relatively short time
define momentum
momentum momentum of an object is its property which organelles due to combined effect of mass and velocity and its measurement is done by the product of mass and velocity.
its unities is kg m/s and it is a vector quantity
its unities is kg m/s and it is a vector quantity
write Newton's third law of motion
Every action has equal and opposite reaction action and reaction both work on different bodies
Sunday, 26 April 2020
write Newton's second law of motion
The acceleration produced in a body by an unbalanced force is proportional to the force and inversely proportional to the mass of the body. The direction of acceleration is always in the direction of force.
what is friction force
When an object moves on a surface aur tries to move on it and opposite force act on the surface of contact with rssists moment or tries to do so. This force is called as a friction force
define inertia
that property that property of an object due to which it remains at rest if it is at rest or it remains in motion is it is in motion is called as inertia
what is an unbalance force
If the resultant force of many forces acting on it is not zero these force are called as unbalanced force
what is balanced force
Is the resultant force of many forces acting on a body is zero then all those force are called as balanced force
define force
That physical factor what bring about change in the conditions of waste and velocity or tries to bring about such changes is called as force it can change save and the state of an object.
The SI unit of force is Newton. It is a vector quantity
The SI unit of force is Newton. It is a vector quantity
what is uniform circular motion
If an object moves on a circular path with uniform speed its motion is called uniform circular motion
what is non uniform acceleration
If there is an equal or variable change in velocity with equal change in the acceleration is called non uniform
what is uniform acceleration
the rate of change of velocity of a moving body is always equal with the rate of change of velocity of a moving body is always equal with a small period of time that celebration of body is called uniform
when will you say a body is in non uniform acceleration
if the rate of change of velocity of a moving body is different or variable with changing a small period of times the acceleration of the body is called as non uniform
when will you say a body is in uniform acceleration
If the rate of change of velocity of a moving body is always uniform with small time periods the acceleration of the body is called as uniform
what is acceleration
the rate of change of velocity is called as acceleration this is indicated by a.
a = (v-u)/t
a = (v-u)/t
what is a speed time graph
The graph plotted on axis X and Y taking time and speed respectively is called as a speed time graph
what is average speed
The distance travelled by an object in unit period of time is called as average speed.
Or,
the ratio between Total distance the ratio between Total distance and total time covered by a moving body is called as a speed.
Average speed = Total distance travelled/ total time taken
Or,
the ratio between Total distance the ratio between Total distance and total time covered by a moving body is called as a speed.
Average speed = Total distance travelled/ total time taken
what do you mean by relative velocity
When two object move the velocity of one object is respect to other is called as relative velocity
what do you mean by linear motion
When an object moves along a linear path if motion is called as motion in a straight line example motion of motor vehicle
what do you mean by circular motion
when an object moves along a circular path it motion is called as circular motion example motion of a fan
what is the meaning of variable motion mention one example
is motion of a body is with changing time periods it is called as variable motion example a vehicle moving on road
what is the meaning of uniform motion can you mention any one example of having uniform motion
If motion of a body remain uniform motion is called as uniform motion example motion of rounds of a watch
what do you mean by non uniform velocity
If a moving body travels variable distance in equal period of time or its direction is changed its velocity is called as variable
what do you mean by uniform velocity
If an object moves along a straight line and travels equal distance in equal period of time it is velocity is termed as uniform
what do you mean by displacement
change of position in a fixed direction is called as displacement.
Or,
The lowest distance between initial and final state of an object is called as displacement
Or,
The lowest distance between initial and final state of an object is called as displacement
what do you mean by origin
The position of a point in comparison to which position of an object is estimated is called as origin
what do you mean by Rest
If an object does not change its position with change in time it is called as the state of rest. Example house tree etc
what do you mean by motion
If some one change it position with time it is called as motion. A running boy flying bird etc are example of motions
Sunday, 19 April 2020
what is the range of frequency associated with ultrasound
Sound with frequency more than 20000 Hz is called as ultrasound we cannot hear the sound dolphin bats etc produce such types of sound
what is the range of frequency associated with infrasound
Sound of less than 20 Hz frequency are called as infrasound this sound cannot be heart by a common man
in which of the three media air water or iron does sound travel the fastest at a particular temperature
Sound Travels the fastest in iron 5095 metre per second then Air 346 metre per second and water 1498 metre per second
where is Sonar used
Sonar is used in finding out the object merged into ocean and to measure the depth of Ocean
why is the sound of coming train here when we hear the sound by placing hear on the rail track
sound waves move fast in metal
mention some example of good and bad reflectors of sound
Good reflector :- metal plates plywood wooden strips
bad reflector :- cork, clothes Porous substance
bad reflector :- cork, clothes Porous substance
what is the frequency of human speech
between 60 vibration between 60 vibration per second and 1300 vibration per second
in which form do transverse wave move forward
the Waves move forward in the form of comparison and reflection
what properties should a medium have to produce longitudinal wave
elasticity the medium should have inertia and electricity
what property should be there in the medium for producing transverse wave
The medium should have inertia and elasticity of a space
Saturday, 18 April 2020
Friday, 17 April 2020
define average power
the ratio between Total energy used and total time taken is called as average power
define 1 watt of power
the power which work 1 the power which work one joule in one second is called as one watt.
1 Watt = 1joule/second
1 Watt = 1joule/second
why do our palms become hot when Me rubbed together
kinetic energy of palms is transformed into heat energy
how is energy transformed when a motor vehicle ascends on a hill
from from Kinetic to potential energy
what type of energy transformation takes place when any things falls down
from potential to kinetic energy
what types of energy transformation takes place in an electric bulb
The electric energy is transformed into light and heat energy
a freely falling object eventually stops on reaching the ground what happens to its kinetic energy
the the kinetic energy becomes zero
what are the various energy transformations that occur when you are riding a bicycle
When we run cycle the potential energy is transferred into muscular energy and muscular energy is transferred into mechanical energy
what is the kinetic energy of an object
the energy found in an object due to its motion is called as kinetic energy
define 1 J of work
1 Joule is the amount of work done when one newton force displays an object in the direction of the action line of force upto 1 metre
write an expression for the work done by when a force is acting on an object in the direction of its displacement
Work done = force × displacement
define work
the work done by the force imposed on an object is equal to the product of the amount of force and the distance travelled in the direction of force work has amount but no direction
Subscribe to:
Posts (Atom)