write true or false 1,The force of friction always acts in the same direction to the direction of applied force.2, when a player kicts the fotball it stops due to the applied force 3,the s.i unit of is for ce kgf.4,pressure exerted by gases increases with increasing height .5,the frication offered by the wheels is called sliding frication.6,the body of fishes and birds are streamlined to reduce the frication in fluids.7,frication between the two surfy can be reduced by polishing the surfaces.
Answers
Answer:
1 according to me it is true 4 is
1.False (because friction force always acts in the direction opposite to that of the object in motion)
2.False (the football stops due to frictional force)
3.False (s.i. unit of force is Newton-N)
4.False (The pressure exerted by the gas can be increased by: increasing the number of collisions of gas molecules per unit time by increasing the number of gas molecules; increasing the kinetic energy of the gas by increasing the temperature; or decreasing the volume of the container.)
5.I am not sure about this because A wheel or ball on a surface is held there by static sliding friction. In order to start the rolling motion, a force or torque must be applied to the wheel. The force of the static sliding friction prevents the wheel from sliding and thus initiates the rolling motion.
6.True(fishes and birds which move through fluids have bodies of special shape, called streamlined shape, so as to reduce the friction due to fluid and avoid energy loss.)
7.True (Friction is reduced by polishing the surface, as polishing makes the surface smooth).