Answer:
Option D
670 Kg.m/s
Explanation:
Initial momentum is given by mv=82*5.6=459.2 Kg.m/s (taking eastward as positive)
Final momentum is also mv but v being westward direction, we take it negative
Final momentum=82*-2.5= -205 Kg.m/s
Change in momentum=Final momentum-Initial momentum=-205-459.2=-664.2 Kg.m/s
Impulse=change in momentum=664.2 Kg.m/s rounded off as 670 Kg.m/s
The answer is definitely C.) their molecules move at the same average speed
Answer:
5.62 m/s
Explanation:
Newton's law of motion can be used to determine the maximum speed of the elevator. In the question, we are given:
Force exerted by the elevator (R) = 1.7 times the weight of the passenger (m*g)
Thus: R = 1.7*m*g
Distance (s) = 2.3 m
Newton's second law of motion: R - m*g = m*a
1.7*m*g - m*g = m*a
a = 0.7*m*g/m = 0.7*g = 0.7*9.8 = 6.86 m/s²
To determine the maximum speed:



Therefore, the elevator maximum speed is equivalent to 5.62 m/s.
Answer:
The distance the bungee cord that would be stretched 0.602 m, should be selected when pulled by a force of 380 N.
Explanation:
As from the given data
the length of the rope is given as l=30 m
the stretched length is given as l'=41m
the stretched length required is give as y=l'-l=41-30=11m
the mass is m=95 kg
the force is F=380 N
the gravitational acceleration is g=9.8 m/s2
The equation of k is given by equating the energy at the equilibrium point which is given as

Here
m=95 kg, g=9.8 m/s2, h=41 m, y=11 m so

Now the force is
or

So here F=380 N, k=630.92 N/m

So the distance is 0.602 m
Doing a force balance on the car:
ma = Fr
ma = μmg
a = μg
a = 0.3(9.81)
a = 29.43 m/s2
Using the formula:
2ax = v2
2(29.43)(34) = v2
v = 44.74 m/s = 161.05 km/h
The car was going 44.74 m/s or 161.05 kph when the brakes were applied.