Answer:
C)-16 N
Explanation:
concepts used
force = mass* acceleration
equation of motion

where v is the final velocity
u is the initial velocity
and s is the distance moved
______________________________________________
Given
mass = 1 kg
initial velocity (u) = 40m/s
final velocity (v) = 0 as stones comes to rest
distance moved by stone (s) = 50m
using 

Thus, acceleration is -16 m/s^2
here acceleration is negative as force of friction is opposing the motion.
Force of friction = mass of stone * acceleration of stone
Force of friction = 1*-16 kgm/s^2 = -16N ( kgm/s^2 = 1 N)
Thus, option c -16N is correct choice.
Answer:
23.5
Explanation:
Dunno how 2 explain but this is correct 4 sureeeeee.
Answer:
0.124 m
Explanation:
the period of a simple pendulum with a small amplitude is given as
T = 2π [√(I/mgd)]
From the above stated formula,
I = moment of inertia
m = mass of the pendulum
g = acceleration due to gravity, 9.8 m/s²
d = distance from rotation axis due to center of gravity
Also, moment of Inertia, I = 2mr², if we substitute this in the above formula, we have
T = 2π [√(2mr²/mgd)]
If we assume that our r = d, then we have
T = 2π [√(2r/g)]
If we make r the subject of the formula in the above equation, we get
r = gT² / 8π²
r = (9.8 * 1²) / 8 * π²
r = 9.8 / 78.98
r = 0.124 m
Thus, the radius of the hoop is 0.124 m
Answer:
a) 1.95 m/s
b) 5.56 m
Explanation:
Given that:
Velocity of the skier
= 14.3 m/s
For the skier moving in the direction of the wave, we have:
Period (T) = 0.450 s
Relative velocity (V) of the skier in regard with the wave = 
where:
= velocity of the skier
= velocity of the wave
The wavelength
can be written as:

---------------> Equation (1)
For the skier moving opposite in the direction of the wave, we have:
Period (T) = 0.342 s
Relative velocity (V) of the skier in regard with the wave = 
The wavelength
can be written as:

------------------> Equation 2
Equating equation (1) and equation (2) and substituting
= 14.3 m/s ; we have:


Collecting the like terms; we have:







b)
The Wavelength of the wave can be calculated using : 



λ ≅ 5.56 m