Answer:
This new element belongs to the group 2.
Explanation:
In the periodic table, the vertical columns are called groups (or families). The elements in the same group share similar chemical and physical properties.
One of these properties is the same amount of outer valence electrons.
For example, in the group 1 the elements have 1 outer valence electron (If we assume that the element is in a neutral state which is without electrical charges).
If this new element has 2 electrons in its outer level it will belong to the group 2. The group 2 is well-known as alkaline earth metals.
For example, the magnesium (Mg) and the calcium (Ca) belong to the group 2.
Answer: The kinetic energy of the ball at the maximum height is zero.
Explanation -
As per the question, the ball is moving vertically upwards. Every time it's velocity will decrease and it becomes zero at the maximum height.
Whole of ball's initial kinetic energy is converted into potential energy at maximum height.
Thus we can conclude that the kinetic energy is zero at the maximum height.
b. destructive interference
c. standing wave formation
d. constructive interference
Answer: The correct answer is destructive interference.
Explanation:
Interference is the phenomenon in which there is a superposition of the waves. If the amplitude of the resultant wave is more than the original wave then there will be constructive interference.
If the amplitude of the resultant wave is lower than the original wave then there will be destructive interference.
Suppose two waves collide and the temporary combined wave that results is smaller than the original waves.
Therefore, the correct option is b.
b. electricity.
c. moving charges.
d.
b. and
c.
Answer:
v=8m/s
Explanation
The initial velocity, u, of the car=32m/s
Since the car has decelerated, we negate the acceleration
This implies that,
Time,t=4s
Let v be the final velocity,
using the relation,
We obtain the below by substitution
By cross multiplying we obtain,
v=8m/s