Answer:
b. it has the same centripetal acceleration as car A.
Explanation:
According to the question, the data provided is as follows
Constant speed of car A = 20 m/s
Constant tangential acceleration until its speed is 40 m/s
Based on the above information, the true statement is the same centripetal acceleration as car A because
As we know that
Centripetal acceleration is
where,
= velocity
r = radius of the path
Now if both car A and car B moving in the same or identical circular path having the same velocity so in this case there is the same centripetal acceleration for that particular time
hence, the second option is correct
A. 409 Hz
The fundamental frequency of a string is given by:
where
L is the length of the wire
T is the tension in the wire
m is the mass of the wire
For the piano wire in this problem,
L = 0.400 m
T = 1070 N
m = 4.00 g = 0.004 kg
So the fundamental frequency is
B. 24
For this part, we need to analyze the different harmonics of the piano wire. The nth-harmonic of a string is given by
where 
is the fundamental frequency.
Here in this case
A person is capable to hear frequencies up to
So the highest harmonics that can be heard by a human can be found as follows:
Mechanical waves nees a material medium to propagate
Electromagnetic waves can propagate in vaccum
HBr is the most powerful and dangerous acid .
Explanation:
A strong acid is one that instantly disunites or grants its protons in suspension. HBr is a strong acid. HBr is powerful than HCl or HF because the overlapping of a 1s-orbital and a 4p-orbital is surprisingly small, thus the binding is weak so splitting is very easy..
