13.0m/s
1.2m/s
Explanation:
Given parameters:
Initial speed of the body = 7.1m/s
time taken = 2.23s
Acceleration = 2.64m/s²
Unknown:
Final speed = ?
Solution:
Acceleration is the rate of change of velocity with time.
a = 
a = acceleration
V = final speed
U = initial speed
T = time taken
Input the variables and solve for V;
2.64 = 
V - 7.1 = 5.9 expression 1
V = 5.9 + 7.1 = 13.0m/s
B
Using the same parameters, the speed after a uniform deceleration of -2.64m/s², the negative sign implies deceleration;
from expression 1;
V - 7.1 = -5.9
V = -5.9 + 7.1 = 1.2m/s
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Acceleration brainly.com/question/3820012
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Answer:
Vr = 20 [km/h]
Explanation:
In order to solve this problem, we have to add the relative velocities. We must remember that velocity is a vector, therefore it has magnitude and direction. We will take the sea as the reference measurement level.
Let's take the direction of the ship as positive. Therefore the boy moves in the opposite direction (Negative) to the reference level (the sea).
![V_{r}=30-10\\V_{r}=20 [km/h]](https://tex.z-dn.net/?f=V_%7Br%7D%3D30-10%5C%5CV_%7Br%7D%3D20%20%5Bkm%2Fh%5D)
Answer:
a) Not Accurate
b) Not Accurate
c) Accurate
d) Accurate
Explanation:
Part a
Not Accurate, because destructive interference would lead to maximum possible magnitude of < 3 m
Part b
Not Accurate, because constructive interference would lead to minimum possible magnitude of > 2 m
Part c
Accurate, because destructive interference would lead to maximum possible magnitude of < 3 m by varying the phase difference between two waves she can achieve the desired results.
Part d
Accurate, because constructive interference would lead to minimum possible magnitude of > 2 m by varying the phase difference between two waves she can achieve the desired results.
The final mass after decay can be obtained by using under given relation:
half life period of As-81 = 33 seconds
mf = mi x (1/2^n)
= 100 x ( 1/2^(43.2/33))
= 40.4 %
Answer:27 km per hour West + 17 km per hour North
