here given that object is dropped from height h = 50 m
So here we can say
initial speed is ZERO
acceleration is due to gravity
now in order to find time to reach the ground we can use kinematics

now plug in all values in it


so it will take 3.2 s to reach the ground
Answer:
The negative sign represents the flow of charge in an opposite direction relative to point of action.
The dependence of a measured value on a controlled value should be the correct answer.
Answer:
a. F = 245 Newton.
b. Workdone = 392 Joules.
c. Power = 196 Watts
Explanation:
Given the following data;
Mass = 25kg
Distance = 1.6m
Time = 2secs
a. To find the force needed to lift the mass (in N );
Force = mass * acceleration
We know that acceleration due to gravity is equal to 9.8
F = 25*9.8
F = 245N
b. To find the work done by the student (in J);
Workdone = force * distance
Workdone = 245 * 1.6
Workdone = 392 Joules.
c. To find the power exerted by the student (in W);
Power = workdone/time
Power = 392/2
Power = 196 Watts.
Answer:
5 fringes option C
Explanation:
Given:
- The wavelength of blue light λ = 450 nm
- The split spacing d = 0.001 mm
Find:
How many bright fringes will be seen?
Solution:
- The relationship between the wavelength of the incident light, grating and number of bright fringes seen on a screen is derived by Young's experiment as follows:
sin(Q) = n* λ / d
Where, n is the order of bright fringe. n = 0, 1, 2, 3, ....
- We need to compute the maximum number of fringes that can be observed with the given condition and setup. Hence we will maximize our expression above by approximating sin(Q).
sin(Q_max) = 1
Q_max = 90 degree
- Hence, we have:
n = d / λ
- plug values in n = 0.001 *10^-3 / 450*10^-9
n = 2.222
- Since n order number can only be an integer we will round down our number to n = 2.
- Hence, we will see a pair of bright fringes on each side of central order fringe.
- Total number of fringes = 2*2 + 1 = 5 fringes is total ... Hence, option C