Year 1972
if I'm not wrong :)
Answer:
a

b
The value is 
Explanation:
From the question we are told that
The mass is
The spring constant is 
The instantaneous speed is 
The position consider is x = 0.750A meters from equilibrium point
Generally from the law of energy conservation we have that
The kinetic energy induced by the hammer = The energy stored in the spring
So

Here a is the amplitude of the subsequent oscillations
=> 
=> 
=> 
Generally from the law of energy conservation we have that
The kinetic energy by the hammer = The energy stored in the spring at the point considered + The kinetic energy at the considered point

=> 
=> 
The correct answer of this question is : A) Change alternating current into direct current.
EXPLANATION :
As per the question, we are given vacuum tube. Vacuum tube can be of various types. Normally it contains two electrodes called cathode and anode which are enclosed in an evacuated glass chamber . There are also other types of vacuum tubes which contain extra electrodes like control grid .
The vacuum tube can be used as a rectifier. It means that it can be used as an electronic device which will convert alternating current into direct current. It may be a half wave rectifier or a full wave rectifier. Actually the direct current obtained during the rectification of alternating current is pulsating in nature.
Hence, the correct answer is that a vacuum tube can be used to change alternating current into direct current.
Answer: d. 8.25 m/s
Explanation:
We are given that Current= 5 m/s in j direction
Velocity= 8 m/s i + 3 m/s j
Now, we have to find Jada's speed with respect to the water.
First we find Jada's velocity with respect to water
v= (8 i + 3 j) - (5 j)
v= 8i - 2 j
To find the speed, we take the magnitude of this velocity vector we have
|v|= 
|v|=
= 8.246 m/s
which comes out to be around = 8.25 m/s
So option d is correct.
Answer:
F = 11 N
Explanation:
Given,
Mass of a block, m = 5 kg
Acceleration of the block, a = 2.2 m/s²
We need to find the force on the person's hand. Let it is F. We know that force is given by the product of mass and acceleration as follows :
F = ma
F = 5 kg × 2.2 m/s²
F = 11 N
So, the force on a person's hand is 11 N.