Answer:
a) 0.022%
b) 10014.32 lb
Explanation:
a) Percentage uncertainty would be
Percent uncertainty is 0.022%
b) For 1 kg uncertainty mass in kg would be
Mass in pounds would be
Mass in pound-mass is 10014.32 lb
Answer:
The work done to get you safely away from the test is 2.47 X 10⁴ J.
Explanation:
Given;
length of the rope, L = 70 ft
mass per unit length of the rope, μ = 2 lb/ft
your mass, W = 120 lbs
mass of the 70 ft rope = 2 lb/ft x 70 ft
= 140 lbs.
Total mass to be pulled to the helicopter, M = 120 lbs + 140 lbs
= 260 lbs
The work done is calculated from work-energy theorem as follows;
W = Mgh
where;
g is acceleration due gravity = 32.17 ft/s²
h is height the total mass is raised = length of the rope = 70 ft
W = 260 Lb x 32.17 ft/s² x 70 ft
W = 585494 lb.ft²/s²
1 lb.ft²/s² = 0.0421 J
W = 585494 lb.ft²/s² = 2.47 X 10⁴ J.
Therefore, the work done to get you safely away from the test is 2.47 X 10⁴ J.
Answer:
The distance travel by block before coming to rest is 0.122 m
Explanation:
Given:
Mass of block 
kg
Initial speed of block 
Final speed of block 
Coefficient of kinetic friction 
Ramp inclined at angle 
28.4°
Using conservation of energy,
Work done by frictional force is equal to change in energy,
Where 
m
Therefore, the distance travel by block before coming to rest is 0.122 m
The answer would be:
C. An unbalanced force has acted on the vehicle.
The presence of an unbalanced force will accelerate an object, the second law of motion dictates this (Although not explicitly). Lets knock out the rest of the choices.
If a balance force acted on the vehicle, then the vehicle would be at rest. The mass of the vehicle did not change (Unless it falls apart, which I doubt). The direction of the vehicle does not change and it will only do so if another force and a stronger one at that will counteract the current net force acting on the vehicle.
Hope you got your answer here, although you did not ask for an explanation, maybe this will help you figure some of the other questions you have on your own.
