Answer:
a 
b
Explanation:
Generally the force constant is mathematically represented as

substituting values given in the question
=> 
=> 
Generally the workdone in stretching the spring 3.5 m is mathematically represented as

=> 
=> 
Generally the workdone in compressing the spring 2.5 m is mathematically represented as
=>
=>
Answer:
v_2 = 2*v
Explanation:
Given:
- Mass of both charges = m
- Charge 1 = Q_1
- Speed of particle 1 = v
- Charge 2 = 4*Q_1
- Potential difference p.d = 10 V
Find:
What speed does particle #2 attain?
Solution:
- The force on a charged particle in an electric field is given by:
F = Q*V / r
Where, r is the distance from one end to another.
- The Net force acting on a charge accelerates it according to the Newton's second equation of motion:
F_net = m*a
- Equate the two expressions:
a = Q*V / m*r
- The speed of the particle in an electric field is given by third kinetic equation of motion.
v_f^2 - v_i^2 = 2*a*r
Where, v_f is the final velocity,
v_i is the initial velocity = 0
v_f^2 - 0 = 2*a*r
Substitute the expression for acceleration in equation of motion:
v_f^2 = 2*(Q*V / m*r)*r
v_f^2 = 2*Q*V / m
v_f = sqrt (2*Q*V / m)
- The velocity of first particle is v:
v = sqrt (20*Q / m)
- The velocity of second particle Q = 4Q
v_2 = sqrt (20*4*Q / m)
v_2 = 2*sqrt (20*Q / m)
v_2 = 2*v
Answer: (d)
Explanation:
Given
Mass of object 
Speed of object 
Mass of object at rest 
Suppose after collision, speed is v
conserving momentum

Initial kinetic energy

Final kinetic energy

So, it is clear there is decrease in kinetic energy . Thus, energy decreases and velocity becomes 2 m/s.
Answer:
answer is DE I hope it will help you please follow me
Answer:
Option b. is correct
Explanation:
An RLC electrical circuit consists of constituent components: a resistor (R), an inductor (L), and a capacitor (C). A resistor, an inductor, and a capacitor are connected in series or parallel.
The impedances of the circuit elements depend on the frequency.
Both impedance magnitudes decrease when the frequency increases