Answer:
The family in the first period is the alkali metal family.
Answer:
the focal length of the mirror is : 
Explanation:
Use the formula for the formation of image using a divergent mirror and recalling that the image (s') that this mirror formed is virtual, so it is entered as a negative number in the formula. Use the object position (s) as 10, the image position (s') as -2, and derive the value of the focal length:
Answer:
C. Beats
Explanation:
When waves are interfering with each other, the sound is louder in some places and softer in others. As a result, we hear pulses or beats in the sound.
Answer:
I don't know this answer because I am not American
Answer:
The force exerted is 318.86 N
Explanation:
The force exerted by such a stream is calculated by multiplying the mass flow rate of water by the velocity of the stream of water.
mass flow rate = 21.4 kg/s
velocity = 14.9 m/s
Force exerted = 21.4 kg/s × 14.9 m/s = 318.86 kgm/s^2 = 318.86 N
