Elizabeth, weight formula is 624 divided by 9.8 which is greater than 57kg
There are several information's already given in the question. Based on those information's the answer can be easily deduced.
Speed of the truck = 70 kph
= 19.44 m/s
Speed of sound = 343 m/s
Then
Observed frequency = 400 Hz ∗ 343 m/s/<span>19.44m/s + 343 m/<span>s
= 378.54
= 379 Hz</span></span>
Answer:
Explanation:
Given
Average Electric Field Strength 
Considering charge distribution to be uniform and earth to be symmetrical
Using Gauss law


Also 
here Electric Field is acting inward therefore

Answer:
The distance represents the difference of the first position and last position of the body.
Explanation:
For example, if y axis represents the position axis, and the first position is 3, second 9 we can see that the distance is a (positive) projection of one position into another. 9-3=6
Hope this helps.