Alkali Metals ......................................
Answer:
560 m/s
Explanation:
Given,
Frequency ( f ) = 80 hz
Wavelength ( λ ) = 7.0 m = 7m
To find : Velocity ( v )
Formula : -
v = f λ
v = 80 x 7
v = 560 m/s
Hence, the velocity of the wave is 560 m/s.
Answer: 
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.
Q = Heat absorbed=
Joules
m= mass of copper = 454 g
c = specific heat capacity = 
Initial temperature of the copper = 
= 23.0°C
Final temperature of the water = 
= ?
Change in temperature ,
Putting in the values, we get:
The final temperature of copper will be
If a Substance conducts heat easily then it is considered a good conductor, since the electrons can move freely within the substance.
Q: ken, 0.75 kg, moves toward a wall (his path normal to the wall) at 52 m/s. 13.0 ms after he touches the wall he pushes himself off in the opposite direction at 60 m/s. What is the magnitude of the average force the wall exerts on Ken during this rapid maneuver
Answer:
-6461.54 N
Explanation:
From Newton's Fundamental equation,
F = m(v-u)/t.................... Equation 1
Where F = Force exerted in sonic, m = mass of ken, v = final velocity, u = initial velocity, t = time.
Given: m = 0.75 kg, v = - 60 m/s (opposite direction), u = 52 m/s, t = 13 ms = 0.013 s
Substitute into equation 1
F = 0.75(-60-52)/0.013
F = 0.75(-112)/0.013
F = -84/0.013
F = -6461.54 N
Note: The negative sign tells that the force act in opposite direction to the initial motion of ken.
Hence the magnitude of the average force of the wall = -6461.54 N
