Answer:
the electric field direction should be in positive y axis
Explanation:
Lets assume that charge on particle is positive and it isequal to +q
First calculate the magnetic force on it
for direction
use Right Hand Rule which will give the direction and by using his the direction will come towards negative y axis.
As given in the question that charge particle does not change their velocity so we need to apply electric field in such a way that electric force direction should be opposite to the magnectic field.
and magnitude should be same as magnectic force and also direcion of electric force depend on the direction of elecric field when charge is positive because electric force 
Hence the electric field direction should be in positive y axis
At one later moment, its speed is 1. 20Mm/s (non relativistic because v is much less than the speed of light).
Doppler Effect is required to solve the problem. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. The general formula of observed frequency, due to Doppler's effect is as follows,
= Frequency observed by observer
v = Velocity of Sound
= Velocity of observer
= Velocity of source
= Frequency of source
PART A) Replacing our values we have that,
PART B) Here the same procedure is performed but this time repeated in the opposite direction.
C) 15 J because it cannot gain energy or lose mass
Answer: Geologists map out <em>data </em>from previous earth quakes to determine earthquakes risk.
Explanation:
Geology is the study of earth. Also, it is the study of how Earth's materials, structures etc are changed over time.
Geologist is a scientist who studies the structure of earth, rocks, soil, fossils and earthquake. So, they map out the data from previous earthquakes to determine earthquake risk.
