Answer:
The velocity of the penny at 25th second is, v = 245 m/s
Explanation:
Given,
The time taken by the penny to hit the ground is, t = 30 s
The initial velocity of the penny, u = 0 m/s
The velocity of the penny at 25th second, v = ?
Using the II equation of motion, the displacement is given by the formula
<em> S = ut + ½ gt²</em>
= 0 + ½ x 9.8 ( 25²)
= 3062.5 m
Using the III equations of motion
<em>v² = u² + 2gs</em>
Substituting the given values,
v² = 0 + 2 x 9.8 x 3062.5
= 60025
v = 245 m/s
Hence, the velocity of the penny at 25th second is, v = 245 m/s
Answer:
Thus, the change in the weight of the person is 1.6N , option c is correct.
Explanation:
Answer:
Induced emf,
Explanation:
It is given that,
Rate of change of magnetic field,
A UHF antenna is oriented at an angle of 47° to a magnetic field, θ = 47°
Diameter of the antenna, d = 13.4 cm
Radius, r = 6.7 m = 0.067 m
We need to find the induced emf of the antenna. It is given by :
Where
= magnetic flux,
So,
B = magnetic field
So, the induced emf of the antenna is 2.2 mV. Hence, this is the required solution.