Answer:
a

b

c

Explanation:
From the question we are told that
The frequency is 
The length of the vibrating string is 
The mass is 
Generally the wavelength is mathematically represented as

=> 
=> 
Generally the wave speed is

=> 
=> 
Generally the tension on the wire is mathematically represented as

=> 
=> 
Answer:
Explanation:
"The thermal energy moving from her coffee to the tongue" represent the heat.
Here coffee is at high temperature while tongue is at low temperature, when Ixchelt tongue make contact with coffee then thermal energy of coffee is absorbed by tongue and tongue gets burned.
As heat always from high Potential to low that is why heat is absorbed by tongue.
Answer:
Explanation:
a )
Time to reach the speed of 20 m/s with an acceleration of 2 m/s² can be calculated as follows .
v = u + a t
20 = 0 + 2 t
t = 20 /2 = 10 s .
Total time = 10 s + 20 s + 5 s = 35 s .
b) Average velocity = Total distance travelled / total time
Distance travelled in first 10 s
S₁ = ut + 1/2 a t²
= 0 + .5 x 2 x 10²
= 100 m
Distance travelled in next 20 s
S₂= 20s x 20 m/s = 400 m
Distance travelled in last 5 s .
deceleration in last 5 s
v = u + at
0 = 20 m/s + a x 5
a = - 4 m/s²
v² = u² - 2 a s
0 = (20 m/s)² - 2 x 4 m/s² x s
s = 50 m
S₃ = 50 m
Total distance = S₁ + S₂ + S₃
= 100 m + 400 m + 50 m
= 550 m .
Average velocity = 550 m / 35 s
= 15.71 m /s .