Answer:

Explanation:
The acceleration of an object is the rate of change of velocity of the object.
Mathematically, it is calculated as:

where
u is the initial velocity
v is the final velocity
t is the time taken for the velocity to change from u to v
Acceleration is a vector, so it is important to also take into account the direction of the velocity.
For the particle in this problem, we have:
u = +48 m/s is the initial velocity (positive direction)
v = -92 m/s is the final velocity (negative direction)
t = 4.5 s is the time interval
Therefore, the average acceleration is

Compounds are atoms or molecules that are chemically bonded together to form a different molecule or compound. The process could be written as a chemical reaction. A mixture is when two elements or compounds are mixed together but do not react, ie no chemical reaction between the two occurs.
Answer:Electromagnetic Energy Example One
activity: cellphones
type of electromagnetic: radio waves
description: we all use our phones to make phone calls and to send a text!
Electromagnetic Energy Example two
activity: microwave
type of electromagnetic: microwave radiation
description: The microwave radiation is absorbed by water molecules in the food which converts to heat intern heats the food do to high levels of radiation being emitted into the food!
Explanation:
i hope this helps you sorry if it doesn't
Answer:
The frequency of sound heard by the boy is 1181 Hz.
Explanation:
Given that,
Frequency of sound from alarm 
Speed = -8.25 m/s
Negative sign show the boy riding away from the car
Speed of sound = 343
We need to calculate the heard frequency
Using formula of frequency

Where,
= frequency of source
= speed of observer
= speed of source
= speed of sound
Put the value into the formula

here, source is at rest


Hence, The frequency of sound heard by the boy is 1181 Hz.
Answer:
5.7 x 10^12 C
Explanation:
Let the charge on earth and moon is q.
mass of earth, Me = 5.972 x 10^24 kg
mass of moon, Mm = 7.35 x 10^22 kg
Let d be the distance between earth and moon.
the gravitational force between them is

The electrostatic force between them is

According to the question
1 % of Fg = Fe



q = 5.7 x 10^12 C
Thus, the charge on earth and the moon is 5.7 x 10^12 C.