Answer:
0.147 J
Explanation:
The total energy that has been transformed into thermal energy is equal to the loss of gravitational potential energy between the initial situation (bob at h=0.5 m above the ground) and the final situation (bob back but at h=0.45 m above the ground).
Therefore, we have

where
m = 0.3 kg is the mass of the bob
g = 9.8 m/s^2
h1 = 0.5 m is the initial height
h2 = 0.45 m is the final height
Substituting, we find the thermal energy

Therefore, the energy transformed into thermal energy is 0.147 J.
According to momentum conservation
15*3 = 45kgm/s
and the velocity of 5 kg mass will be
45/5 = 9 m/s
Answer:
Scalar quantity. a) 35 m
Explanation:
Scalars and vectors are the geometrical representation of a physical quantity. Some physical quantities are scalars and others are vectors.
The physical quantities that are fundamental or derived belong to either of these categories.
The basic nature of a scalar is that it is expressed only with the magnitude.
The nature of a vector is that it has a magnitude as well a definite direction.
The basic way to differentiate a physical quantity whether it is a scalar or vector is to look for direction. If it has a direction, then it is a vector quantity or else it is a scalar. It is notable that every physical quantity has a magnitude.
Hence, the scalar quantity in the given list is a). 35 m