Answer:
The force of gravity exerts a downward force. The floor exerts an upward force. Since these two forces are of equal magnitude and in opposite directions, they balance each other.
Answer:
2Ω
Explanation:
If a 18Ω resistance is cut into three equal parts each of the resistance will be 18Ω/3 = 6Ω
Equivalent ratio in parallel is expressed as:
1/R = 1/6 + 1/6 + 1/6
1/R = 3/6
Cross multiply
3R = 6
R = 6/3
R = 2Ω
Hence the required equivalent resistance is 2Ω
Answer: Heterogeneous mixture - the parts are not uniformly mixed.
A mixture contains components having distinct chemical properties. There are two types of mixtures: homogeneous and heterogeneous. In a homogeneous mixture there is uniform distribution of components. we cannot distinguish one portion of the mixture from another. for example salt mixed in water. In heterogeneous mixture, the components are not uniformly mixed. hence, we are able to distinguish different parts of a mixture, like the mixture of iron, sand and salt given in this question.
Answer:
(a) 62.5 m
(b) 7.14 s
Explanation:
initial speed, u = 35 m/s
g = 9.8 m/s^2
(a) Let the rocket raises upto height h and at maximum height the speed is zero.
Use third equation of motion


h = 62.5 m
Thus, the rocket goes upto a height of 62.5 m.
(b) Let the rocket takes time t to reach to maximum height.
By use of first equation of motion
v = u + at
0 = 35 - 9.8 t
t = 3.57 s
The total time spent by the rocket in air = 2 t = 2 x 3.57 = 7.14 second.
ANSWER: d) 8
EXPLANATION: Two sets of two shared electrons (4 electrons total shared) = one set of a double covalent bond.
Therefore, 8 electrons total shared = two sets of double covalent bonds