Answer: A) chemical - gas produced
Explanation: Physical change is a process in which there is no change in chemical composition of the substance.
Chemical change is a process in which there is a change in chemical composition of the substance.
Chemical process is accompanied by following changes
1. Change in color
2. Absorption or release of energy
3. Production of gas
4. Formation of precipitates.
Thus a chemical reaction is happening on mixing baking soda and vinegar
, there is production of
which expanded the balloon.
Answer:
v = 79.2 m/s
Solution:
As per the question:
Mass of the object, m = 250 g = 0.250 kg
Angle,
Coefficient of kinetic friction,
Mass attached to the string, m = 0.200 kg
Distance, d = 30 cm = 0.03 m
Now,
The tension in the string is given by:
(1)
Also
T = m(g + a)
Thus eqn (1) can be written as:
Now, the speed is given by the third eqn of motion with initial velocity being zero:
where
u = initial velocity = 0
Thus
