Answer:
0.09 N
Explanation:
We are given that
Radius of disk,r=6 cm=
1 m=100 cm
B=1 T
Current,I=3 A
We have to find the frictional force at the rim between the stationary electrical contact and the rotating rim.
Torque due to friction
Where friction force=F
Substitute the values
Answer: 117.8 nm
Explanation:
Given,
Nonreflective coating refractive index : n = 1.21
Index of refraction: = 1.52
Wave length of light = λ = 570 nm =
Hence, the minimum thickness of the coating that will accomplish= 117.8 nm
Answer:
12.7m/s
Explanation:
Given parameters:
Mass of the diver = 77kg
Height = 8.18m
Unknown:
Final velocity = ?
Solution:
To solve this problem, we use one of the motion equations.
v² = u² + 2gh
v is the final velocity
u is the initial velocity
g is the acceleration due to gravity
h is the height
v² = 0² + (2 x 9.8 x 8.18)
v² = 160.3
v = 12.7m/s
Answer:
The answer is "a, c and b"
Explanation:
- Its total block power is equal to the amount of potential energy and kinetic energy.
- Because the original block expansion in all situations will be the same, its potential power in all cases is the same.
- Because the block in the first case has no initial speed, the block has zero film energy.
- For both the second example, it also has the velocity, but the kinetic energy is higher among the three because its potential and kinetic energy are higher.
- While over the last case the kinetic speed is greater and lower than in the first case, the total energy is also higher than the first lower than that of the second.
- The greater the amplitude was its greater the total energy, therefore lower the second, during the first case the higher the amplitude.
Answer : The final temperature is,
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of ice =
= specific heat of water =
= mass of ice = 50 g
= mass of water = 200 g
= final temperature = ?
= initial temperature of ice =
= initial temperature of water =
Now put all the given values in the above formula, we get:
Therefore, the final temperature is,