Answer: it becomes a positive ion
Explanation:
So, when an atom loses 2 electrons there will be no change in the number of neutrons. Therefore, an isotope will not form. Thus, it is concluded that when an atom with no charge loses two electrons, it becomes a positive ion.
Answer:
4.29 millimeters
Explanation:
Bats emit ultrasound waves: in air, ultrasound waves travel at a speed of

The frequency of the waves emitted by this bat is:

Therefore we can find the wavelength of the wave emitted by the bat by using the relationship between speed, frequency and wavelength:

Answer:
K = 960 J
Explanation:
Given that,
Mass of a child = 20 kg
Mass of a sled = 10 kg
Speed of child on sled = 8 m/s
We need to find the kinetic energy of the sled with the child.
The total mass of child and the sled = 20 kg + 10 kg
= 30 kg
The formula for the kinetic energy of an object is given by :

Hence, the kinetic energy of the sled with the child is 960 J.