Physics Conceptual Question - II?

Question

10. Can a body have momentum without having energy or energy without momentum?
11. Pressure is a scalar quantity while forces produced by the action of pressure are vectors. why?
12. Viscosity is an example of transported phenomenon. what property is being transported?
13. Why we become physically tired when we push against a wall, fail to move it and therefore do not work on it.
14. Two unequal masses are attached to the ends of a solid rod. Which mass is nearest to the centre of mass lighter or heavier and why?
15. Is the gravitational force a conservative force?
16. Why do auto manufacturers recommend using different viscosities of engine oil in cold and hot climate?
17. Soap films are much more stable thatn film of water, why?

Answer 1

10)
Having momentum implies having velocity which in turn implies having kinetic energy.
A body cannot have momentum without having energy.
A body can have energy without having momentum.
11)
Pressure* area = Force.
Though pressure is a scalar, area is considered to be a vector and hence the product is a vector.
Any vector can be multiplied by a scalar and is called dot product. The result is a vector but the magnitude of the resultant product vector is different.
12)
Viscosity is the friction between two layers of liquid in motion {transportation]
13)
No mechanical energy is spent, but energy being converted into heat energy and dissipated to the surroundings including the wall.
14)
Moment about the center of mass of both the masses are equal hence greater the mass shorter the distance from the center of mass.
15}
Yes.
16)
Viscosities change with climate [temperature]
17)
Surface tension of soap bubbles is higher than that of water surface.
.

Answer 2

The frequency is on the subject remember of mass and rigidity by using the equation f=(a million/2L)*Root(T/mew) mew is the mass consistent with unit length length is continuous so that's disregarded f ?Root(rigidity) and a million/Root(Mass) apart from Wave velocity v is continuous v=fw the place w is the wavelength So f is proportional to a million/w w ? T^-0.5 w ? m^0.5 w ? Root[m/T] w = kRoot[m/T] ok is merely any consistent m1= 2 m2 and T1 = 8 T2 w1=kRoot[m2/8T2]= 0.5kRoot[m2/T2] w2=kRoot [m2/T2] So w2= 2 w1 the 2d wavelength is two times the 1st one. hence image B is right because of the fact the wavelength (distance between consecutive crests) is doubled interior the 2d wave. *ok = n/2Root[L] incase you have been questioning