Chap-8 Flashcards
What is force?
Force is a pull or a push upon an object
a)Force is a vector quantity that has____ and ___. b)Force also has ___
a) magnitude ; direction
b )point
S.I. unit for force is ?
Newton,(N)
Newton’s Third Law states what ?
Newton’s Third Law states that for every action force, there is a reaction force of the same magnitude but in the opposite direction
Effects of force ?
-Force can change shape, size and motion of the object
1.Moving a stationary object
2.Stopping a moving object
3.Changing the speed of an object that is in motion
4.Changing the direction of an object that is in motion
5.Changing the shape and size of an object
Explain Buoyant Force and Density .
Buoyant force = Actual weight - Apparent weight
1.The denser the object, the lesser the buoyant force than the object. Thus, the object submerge
2.The less dense the object, the higher the buoyant force than the object. Thus, the object float
What is Effort in Lever?
Force applied on the bar
What is Load in Lever?
Object to be moved
What is Fulcrum in Lever?
Fixed support point
How many Classification of levers are there ? Explain them .
FLE
123
What is the formula for The Moment of Force ?
Moment of force = Force(N) x Perpendicular distance from the pivot to the (m)
Define pressure .
Pressure is defined as force per unit area (direction of force is perpendicular to the surface area)
What is S.I unit for pressure ?
pascal (Pa)
What is the formula to calculate pressure ?
Pressure = Force (N) / Surface area (m2)
The frequency of collision between the air molecules and the walls of the container will produce a force that pushes against the walls which is called ?
air pressure / gas pressure
How does volume affect gas pressure ?
Decreasing the volume of a contained gas will increase its pressure, and increasing its volume will decrease its pressure.
How does temperature affect gas pressure ?
When the temperature of the container increases, the kinetic energy of the gas molecule becomes high. This means the collision rate of the particles increases. Due to the collision of gas particles, the pressure increases across the wall of the container.
What is Atmospheric Pressure ?
Atmospheric pressure is the pressure exerted by the atmosphere on the surface of the Earth and all objects on the Earth.
Explain the atmospheric pressure applied to a plunger .
If you press on the plunger, you increase the pressure of the air and thus the air in the balloon contracts or decreases its volume.
Explain the atmospheric pressure applied to a straw .
Since the atmospheric pressure is greater on the outside of the straw, liquid is forced into and up the straw and into your mouth
What is the Relationship between Altitude and Atmospheric Pressure ?
Atmospheric pressure decreases as altitude increases
Effects of Depth on Liquid Pressure applied to a dam ?
The walls of a dam are designed to be thicker at the base in order to withstand the high water pressure at the base of the dam.
Why do divers wear a special suit while diving ? why can’t they wear a normal t-shirt while diving?
A diver wears a special suit in order to withstand high water pressure. Whereas , normal clothing won’t be able to withstand the high water pressure.
