Answer:
D on first page
I think on the second page is also D
The third page is B
Explanation:
Answer:
If an object moves along a straight line, the distance traveled can be represented by a distance-time graph. In a distance-time graph, the gradient of the line is equal to the speed of the object. The greater the gradient (and the steeper the line) the faster the object is moving.
Explanation:
Answer:
The correct answer is d
Explanation:
In this exercise they ask us which statement is correct, for this we plan the solution of the problem, this is a Doppler effect problem, it is the frequency change due to the relative speed between the emitter and the receiver of sound.
The expression for the Doppler effect of a moving source is
f ’= (v / (v- + v_s) f
From this expression we see that if the speed the sound source is different from zero feels a change in the frequency.
The correct answer is d
Answer:2 m right
Explanation:
Given
First child is sitting 1 m left from Pivot point
Mass of second child is half of first
Let mass of first child be m
Second child 
In order to balance see saw torque must be zero about pivot
x=2 m right from pivot point
