Answer:
The acceleration of the platform is - 1.8 m/s²
Explanation:
The net force on a body causes that body to accelerate in the direction of the resultant force applied.
Setting up the force equilibrium for the configuration:
ma = 800 - mg
100a = 800 - 100×9.8
100a = - 180
100a = - 180
a = - 1.8 m/s²
This indicates that the body is falling downward.
Response: a) 0.04 kW = 40 W
b) 0.05
Explanation:
A)
The thermal efficiency of the power cycle is calculated as Input / Output
Input = 10 kW + 14,400 kJ/min which translates to 10 kW + 14,400 kJ/(60s) = 10 kW + 14,400/60 kW.
Output equals 10 kW
Thus, Thermal Efficiency = Output / Input = 10 kW / 250 kW = 0.04 kW = 40 W
B)
Maximum Thermal Efficiency of the power cycle is defined as 1 - T1/T2
where T1 = 285 Kelvin
and T2 = 300 Kelvin
Thus, Maximum Thermal Efficiency = 1 - T1/T2 = 1 - 285/300 = 0.05
Answer:
A) and B) are valid.
Explanation:
When an object remains at rest, it is indicative that no net force acts upon it.
The downward gravitational force from Earth must be counterbalanced by an upward force of equal magnitude in order to maintain rest.
This upward force is provided by the normal force, which adjusts to satisfy Newton’s 2nd Law and is always perpendicular to the surface supporting the object (in this instance, the ground).
At the molecular level, this normal force comes from the ground's bonded molecules acting like tiny springs, compressed by the object’s molecules, providing an upward restorative force.
Thus, statements A) and B) are true.
Calculating the average speed is straightforward by using the formula involving distance and time:
average speed = distance / time
Thus, we have:
average speed = 4875 ft / 6.85 minutes
<span>average speed = 711.68 ft / min</span>
To find the mass using a weight of 1.4 N:
1.4/9.8 = 0.1428 kg
The momentum is calculated as 0.1428 multiplied by 44.7, which is 6.38 kgm/s.
