Distance is the total length covered = 2m + 3m = 5m
Displacement is his distance from original position.
Displacement = 2m + (-3)m. Representing the 3m walked back as -3.
Displacement = 2m - 3m = -1m.
So his displacement is 1m behind his original starting point.
Answer:
I don't think the information is complete
Answer:
10 kg
Explanation:
Assuming a frictionless surface, then force F=ma where F is the applied force, m is the mass and a is acceleration. Making m the subject of the formula then 
Substituting 100 N for the applied force F and 10 m/s^2 for acceleration a then the value of m will be 
Therefore, in terms of kilograms, the bookshelf weighs 10 Kg
Answer:
Constructive Interference.
Explanation:
Constructive Interference.
Definition:
Two waves meet in such a way their highs(Crests) combine to form a new waves whose magnitude is the sum of magnitude of combining waves.
Since two waves have same wavelength and are in phase so when they combine they well form a way which has the magnitude equal to the sum of the magnitude of both waves.
Reasons why it is Constructive Interference:Waves
- Have Same wavelength
- Are in phase (Can have phase difference of 2π
- Have crests aligned with each other (Appear at same point)
Honed I don’t know where the question is