Answer:
Open spaces in water's solid structure makes its solid state less dense than its liquid state.
Explanation:
- Water unlike other liquids is special. It contracts when cooled, down to a temperature of 4°C but thereafter begins to expand as it reaches 0°C and turns into ice.
- This property is useful for the preservation of marine life in very cold temperatures. During winter, the surface water in water lakes and rivers starts cooling. Upon reaching the temperature of 4°C, the surface water descends to the bottom as it denser.
- This help in the maintenance of temperature of the water at the bottom at 4°C. It is in this layer that marine life is sustained.
Answer:
B
Explanation:
Hydrogen is synthesized to water by adding Oxygen.
Hydrogen is oxidised to water by combustion ( burning in presence of oxygen).
Answer:
The condor has a wing span of 10 feet
Explanation:
This can be solved by a simple rule of three
In a rule of three problem, the first step is identifying the measures and how they are related, if their relationship is direct of inverse.
When the relationship between the measures is direct, as the value of one measure increases, the value of the other measure is going to increase too. In this case, the rule of three is a cross multiplication.
When the relationship between the measures is inverse, as the value of one measure increases, the value of the other measure will decrease. In this case, the rule of three is a line multiplication.
In this problem, our measures are the wing span of the condon in meters and the wing span of the condor is feet. As the value of one of these measures increases, the other is going to increase too.
We know that 1m has 3.281 feet,
So we have the following rule of three:
1m - 3.281 feet
3.05m - x feet
x = 3.821*3.05
x = 10 feet
The condor has a wing span of 10 feet
To Find :
The horizontal range of a projectile launched at 15 degrees to the horizontal with speed of 40 m/s.
Solution :
The horizontal range of a projectile is given by :
( Here, g is acceleration due to gravity = 10 m/s² )
Putting all value in above equation :
Therefore, the horizontal range of projectile is 80 m.
