1 year<span> consists of 365 days. 1 day has 24 hours, each hour has 60 minutes and each minute has 60 </span>seconds. <span>1 day = (24 hours/day) × (60 minutes/hour) × (60 seconds/minute) = 86400 seconds/day
Hope that helped :)</span>
Answer:
C.The car appears to be moving 30 km/hr in the opposite direction of the bus.
Explanation:
There are two reference systems involved in this situation:
- Reference system S: this is the reference system where velocities are measured with respect to the ground. In this reference system, the car is parked, so its velocity is
- Reference system S': this is the reference system moving with the bus. This reference system is moving with a velocity of
with respect to the reference system S
Calling
the velocity of the car in the reference system S', we have:

From which

and the negative sign means that a passanger in the bus observes the car moving in the opposite direction.
Answer:
A pipe has a length of 1.15 m.
a) Determine the frequency of the first harmonic if the pipe is open at each end. The velocity of sound in air is 343 m/s. Answer in units of Hz
b) What is the frequency of the first harmonic if the pipe is closed at one end?
Answer in units of Hz
Explanation: