Initially, the spring stretches by 3 cm under a force of 15 N. From these data, we can find the value of the spring constant, given by Hook's law:

where F is the force applied, and

is the stretch of the spring with respect to its equilibrium position. Using the data, we find

Now a force of 30 N is applied to the same spring, with constant k=5.0 N/cm. Using again Hook's law, we can find the new stretch of the spring:
Answer:

Explanation:
The momentum change is defined as:

Taking the downward motion as negative and the upward motion as positive, we have:

Replacing (2) and (3) in (1):

Answer:
1.) 11 km/s
2.) 9.03 × 10^-5 metres
Explanation:
Given that an electron enters a region of uniform electric field with an initial velocity of 64 km/s in the same direction as the electric field, which has magnitude E = 48 N/C.
Electron q = 1.6×10^-19 C
Electron mass = 9.11×10^-31 Kg
(a) What is the speed of the electron 1.3 ns after entering this region?
E = F/q
F = Eq
Ma = Eq
M × V/t = Eq
Substitute all the parameters into the formula
9.11×10^-31 × V/1.3×10^-9 = 48 × 1.6×10^-19
V = 7.68×10^-18 /7.0×10^-22
V = 10971.43 m/s
V = 11 Km/s approximately
(b) How far does the electron travel during the 1.3 ns interval?
The initial velocity U = 64 km/s
S = ut + 1/2at^2
S = 64000×1.3×10^-6 + 1/2 × 8.4×10^12 × ( 1.3×10^-9)^2
S =8.32×10^-5 + 7.13×10^-6
S = 9.03 × 10^-5 metres
Answer:
same
Explanation:
Acc. to Einstien's postulate of special theory of
Relativity ,
Velocity of the light beam is same in all frames of references
(a) If the freight car is at rest
The frame we can assumed as Non - inertial frame of reference
s
In the inertial frame of reference , velocity of the light beam has its own value as : 3 x 10^8 m/s
(b) If the freight car is moving , the frame we can assumed as Non -inertial frame of reference
In thus case also , The velocity of the light beam will also have the same value as ; 3 x 108 m/s
Answer:
19.6 kg*m/s^2 = 19.6 N
Explanation:
Weight is mass times acceleration due to gravity. And hopefully you know that acceleration due to gravity on earth is 9.8 m/s^2 So what is half of that? 4.9. So now the calculation is super simple.
mass = 4 kg and acceleration = 4.9 m/s^2 so now we multiply these two numbers and get 19.6 kg*m/s^2. kg*m/s^2 is also known as Newtons, abbreviated with an N so the final result is 19.6 N.