Quiz 2

If the dimensional formula of physical quantity is MLT^-2, then its measuring unit is ....

• Kg.m.s²

• Kg.m.s^-2

• Kg.m^-1.s²

• Kg.m^-1.s^-2

If the dimensions of the velocity v are M⁰LT^-1 and the kinetic energy = 0.5mv², then the dimensional formula of the kinetic energy is .......

• MLT^-1

• MLT^-2

• ML²T^-2

• none of previous

If the dimensions of quantity x are LT^-1, the dimension of quantity y is M, and the dimensions of quantity z is MLT^-1, the dimensions of 2xy+3z is .....

• MLT^-1

• 5MLT^-1

• M²L²T^-2

• MLT^-2

The dimensional formula of three quantities x, y and z are MLT^-1, MLT^-2 and T, which of the following quantities may be correct?

• z=xy

• z=y/x

• z=x/y

• z=y²/x

The volume of sphere = (4/3) πr³

• may be correct

• must be wrong

The velocity = a t² , where a is the acceleration

• may be correct

• must be wrong

If rod A has length 2±0.1 cm and rod B has length 5±0.1 cm

Then, rod B is longer than rod A by … cm

• 3

• 3±0.1

• 3±0.2

• 7±0.2

In experiment to find physical quantity L by adding two quantities L₁ and L₂

L₁=(4±0.1) m and L₂=(6±0.2) m

The value of L and the relative error are ...

• 10±0.3 , 0.3%

• 2±0.3 , 3%

• 10±0.3 , 0.03%

• 10±0.3, 3%

In experiment to find physical quantity L by adding two quantities L₁ and L₂

L₁=(4±0.1) m and L₂=(6±0.2) m

The value of L and the relative error are ...

• 10±0.3 , 0.3

• 2±0.3 , 3

• 10±0.3 , 0.03

• 10±0.3, 3

If object has mass (100±2) kg and volume (2±0.02) m³ .

Knowing density=mass/volume

The density =  ….. kg/m³

• 50 ±2.02

• 50 ±1.5

• 50 ±0.02

• 50 ±1.98