Answer
40 degrees
Explanation
When waves hit a surface they get reflected. The law of reflection states that the angle of incidence is equal to the angle of reflection. In this case, the law of reflection tells us that if the angle of incidence is 40 degrees, the angle of reflection is 40 degrees.
Answer:
Approximately
(assuming that the car was on level ground.)
Explanation:
When an object of mass
is moving at a speed of
, the kinetic energy of that object would be
.
Initial kinetic energy of the car:
.
After the car comes to a stop, the kinetic energy of this car would be
because the car would not be moving.
Change to the kinetic energy of the car:
.
If the car is traveling on level ground, friction would be the only force that contributed to this energy change. Hence:
.
The value of the work that friction did is negative. The reason is that at any instant before the car comes to a stop, friction would be exactly opposite to the direction of the movement of the car.
The work of a force on an object is the dot product of that force and the displacement of that object. The dot product of two vectors of opposite directions is negative. Hence, in this question, the work that friction did on the car would be negative because the friction vector would be opposite to the movement of the car.
Answer:
V4=9.197v
Explanation:
Given:
V1= 18v ,V2= 12v ,r1=r5=58ohms ,r2=r6=124ohms , r3=47ohms ,r4= 125ohms
V4= I4R4 = V2/(R4 + R5)×R4
V4= 12×125 /(125 + 58)
V4=1500/183 =9.197v
Answer:
C. 1.15
Explanation:
The formula for the critical angle is:
Where,
is the critical angle
is the refractive index of the refractive medium. ( Alcohol , ? )
is the refractive index of the incident medium. ( Glass, 1.66 )
<u>Critical angle = 44º</u>
Applying in the formula as: