Answer:
Explanation:
Given
Velocity of bat 
Frequency of sound 
velocity of sound 
using Doppler Effect apparent frequency is given by

where
apparent frequency
v=velocity of sound in the given media
velocity of source
velocity of observer
here velocity of source is zero
as source is travelling towards source thus

There are six statements on the list.
The first 2 are true, and the last 2 are true.
The 2 in the middle aren't true. They are false.
Answer:
Explanation:
Given
density 
diameter 
Magnetic field 
Force on the current carrying conductor placed in a magnetic field

where L=length of conductor
=angle between magnetic field and current
If the wire is floating then weight must be balanced by weight of wire

Therefore




You could look under a microscope it see what type of minerals they have or substances they have that makes them one .!
The force of friction acts in the opposite direction that the object is moving, so friction slows down the motion of moving objects. Friction also produces unnecessary heat. For example, car engines become hotter because of friction.