Answer:
32cm³
Explanation:
Given parameters:
Density of substance = 2.7g/cm³
Mass of substance = 86.4g
Unknown:
Volume of substance = ?
Solution:
Density is the mass per unit volume of a substance.
Density = 
Since the unknown is volume we solve for it;
mass = density x volume
86.4 = 2.7 x volume
volume =
= 32cm³
Well it is definitely answer B because when light is on for a long time it heats up a lot.the thermometer obviously went up which means the light bulb had more energy and was hotter than the start of it
The current is defined as the amount of charge transferred through a certain point in a certain time interval:

where
I is the current
Q is the charge

is the time interval
For the lightning bolt in our problem, Q=6.0 C and

, so the average current during the event is
Answer:
(a) Wavelength is 0.436 m
(b) Length is 0.872 m
(c) 11.518 m/s
Solution:
As per the question:
The eqn of the displacement is given by:
(1)
n = 4
Now,
We know the standard eqn is given by:
(2)
Now, on comparing eqn (1) and (2):
A = 1.22 cm
K = 

where
A = Amplitude
K = Propagation constant
= angular velocity
Now, to calculate the string's wavelength,
(a) 
where
K = propagation vector


(b) The length of the string is given by:


(c) Now, we first find the frequency of the wave:



Now,
Speed of the wave is given by:

