Answer:
T = 60 s
Explanation:
There are 6 poles on the track which are equally spaced
so the angular separation between the poles is given as


so the angular speed of the train is given as


now we have time period of the train given as



Answer:
a) false b) true c) true d) false and e) true
Explanation:
a) false. All the energy applied is used for the phase change, so the temperature remains constant.
b) true. The kinetic energy is associated with the speed of the particles and they have more mobility in the liquid, therefore, more kinetic energy.
c) true. Since energy is used for state change
d) false. In general, mobility and temperature are proportional
e) true. Heat is the source of energy for the change of state
Answer:
15.4 kg.
Explanation:
From the law of conservation of momentum,
Total momentum before collision = Total momentum after collision
mu+m'u' = V(m+m').................... Equation 1
Where m = mass of the first sphere, m' = mass of the second sphere, u = initial velocity of the first sphere, u' = initial velocity of the second sphere, V = common velocity of both sphere.
Given: m = 7.7 kg, u' = 0 m/s (at rest)
Let: u = x m/s, and V = 1/3x m/s
Substitute into equation 1
7.7(x)+m'(0) = 1/3x(7.7+m')
7.7x = 1/3x(7.7+m')
7.7 = 1/3(7.7+m')
23.1 = 7.7+m'
m' = 23.1-7.7
m' = 15.4 kg.
Hence the mass of the second sphere = 15.4 kg
Different elements require different levels of energy to make or break a bond
We are given with the specific heat capacity of ethanol, the mass of the sample and the temperature change to determine the total amount of heat to raise the temperature. The formula to be followed is H = mCpΔT. Upon subsituting, H = 79 g * 2.42 J/gC *(385-298)C = 16.63 kJ