Explanation:
According to the free body diagram attached below, there are only two forces that are acting upon the block, namely the force tension of the rope acting upwards and the weight of the block acting downwards.
Therefore, the magnitude of the net (resultant) force exerted on the block is
.
Since the magnitude of 
> magnitude of 
, this implies that the block will accelerate upwards.
INDUCTION MOTOR:-
Speed:-Less speed range than PMAC motors • Speed range is a function of the drive being used — to 1,000:1 with an encoder, 120:1 under field-oriented control
Reliability:-Waste heat is capable of degrading insulation essential to motor operation • Years of service common with proper operation
Power density:-Induction produced by squirrel cage rotor inherently limits power density
Accuracy:-Flux vector and field-oriented control allows for some of accuracy of servos
Cost:-Relatively modest initial cost; higher operating costs
PERMANENT MAGNET MORTOR:-
speed:-VFD-driven PMAC motors can be used in nearly all induction-motor and some servo applications • Typical servomotor application speed — to 10,000 rpm — is out of PMAC motor range
Reliability:-Lower operating temperatures reduces wear and tear, maintenance • Extends bearing and insulation life • Robust construction for years of trouble-free operation in harsh environments.
power density:-Rare-earth permanent magnets produce more flux (and resultant torque) for their physical size than induction types.
Accuracy:-Without feedback, can be difficult to locate and position to the pinpoint accuracy of servomotors
<span>Cost:-Exhibit higher efficiency, so their energy use is smaller and full return on their initial purchase cost is realized more quickly</span>
Answer:
Angular momentum = 0.7 kg.m²/s
Angular velocity = 583.3 rad/s
Explanation:
1. The torque τ is related to the angular momentum L by the relation
τ = ΔL/Δt
ΔL = τΔt
τ = 10 N. m
Δt = 70 ms = 70 × 10⁻³s
ΔL = (10 N. m) × (70 × 10⁻³s) = 700 × 10⁻³ kg.m²/s = 0.7 kg.m²/s
2. The rotational inertia I relates the angular momentum L to the angular velocity w
L = Iw
w = L/I
L = 0.7 kg.m²/s
I = 1.2 × 10⁻³ kg.m²
w = (0.7 kg.m²/s)/(1.2 × 10⁻³ kg.m²) = 583.3 rad/s
Answer:B,C,D
Explanation:
Thermodynamic efficiency is given by
efficiency can be increased by Keeping 
constant and increasing 
Keeping constant and decreasing 
by increasing 
by decreasing 
ratio
Answer:
minimum mass of the neutron star = 1.624 × 10^30 kg
Explanation:
For a material to remain on the surface of a rapidly rotating neuron star, the magnitude oĺf the gravitational acceleration on the material must be equal to the magnitude of the centripetal acceleration of the rotating neuron star.
This can be represented by the explanations in the attached document.
minimum mass of the neutron star = 1.624 × 10^30 kg
