This looks like the photo electric effect ... classical physics reckoned that if you shone an intense enough light beam on a metal you could get electrons ejected from the metal (maybe in analogy to thermionic emission - heat). It sort of "forgot" about the frequency and photon/particle nature of light.
Enter the "photo electric" effect experiment, Einstein's explanation, and the Nobel committee having an excuse to award E a Nobel prize, even though said prize was probably more for relativity.
This is very good conceptual question and can clear your doubts regarding work-energy theorem.
Whenever force is perpendicular to the direction of the motion, work done by that force is zero.
According to work-energy theorem,
Work done by all the force = change in kinetic energy.
here, work done = 0.
Therefore,
0=change in kinetic energy
This means kinetic energy remains constant.
Hope this helps
Answer and Explanation:
A. We have temperature t = 32
Speed of sound, s = 1087.5
As t increases by 1⁰f speed increases by 1.2
So that
S = 1088.6
T= 33⁰f
We have 2 equations
1087.5 = k(32) + c
1088.6 = k(33) + c
Subtracting both equations
(33-32)k = 1088.6-1087.5
K = 1.1
b.). S = kT + c
1087.5 = 32(1.1) + c
Such that
C = 1052.3
Therefore
S = 1.1(t) + 1052.3
C.). S = 1.1t + 1052.3
We make t subject of the formula
T = s/1.1 - 1052.3/1.1
T = 0.90(s) - 956.3
D. This means that We have temperature to rise by 0.90 whenever speed is increased
Answer:
6.18 m/s
Explanation:
Roller skate collision
The final direction of the system (me=M + person=P) velocity vector is at an angle; Ф, to the direction running south to north. Apply the component form of the impulse-momentum equation, firstly;
x-axis component form (+x east);
+ 
+ 
= 
+
Ф
60 ·8 + 0 = (60 + 80)
Ф
480 = 140
Ф................. (I)
y-axis component form (+y north);
+ 
+ 
= 
+ 
Ф
0 + 80.9 = (60 + 80)
Ф
720=
140Ф
140Vf=
Ф......................................(2)
Substituting (2) into (1) to give the angle;
480 = 720tan Ф
Ф = arctan(0.67) =33.69°.......................(3)
Evaluating (1) with (3) gives the velocity magnitude
480 = 140Vfsin 33.69°
Vf=6.18 m/s
note 1:
This angle corresponds to a direction; 90° - 33.69° = 56.31° north of east.
A perfect elastic collision is defined as one in which there is no loss of kinetic energy in the collision. An inelastic collision is one in which part of the kinetic energy is changed into another form of energy in the collision. Well hope this answers your question :)
