Масса (килограмм), длина (метр) и время (секунда) - это 3 из 7 основных единиц в системе СИ.
Базовые единицы произвольно определены как то, что они есть, поэтому они не могут быть получены.
Все другие единицы в системе СИ являются производными от 7 основных единиц, таких как скорость (метр / секунда).
Остальные 4 - это температура (Кельвин), количество вещества (моль), электрический ток (ампер) и светимость (кандела).
Answer:
α = 0
, w = w₀
Explanation:
Torque is related to angular acceleration by Newton's second law for rotational motion.
τ = I α
Where τ is the torque, I the moment of inertia and α the angular acceleration.
If we apply an external torque for the sum of all torques to be zero, the angular acceleration must fall to zero
α = 0
Since the acceleration is zero, the angular velocity you have at that time is constantly killed.
w = w₀ + α t
w = w₀ + 0
Answer:
Explanation:
Let m be the mass of Astronaut
M=mass of earth
G=Gravitational constant
R=radius of Earth
Force Exerted by Earth on Astronaut

acceleration due to gravity is 

When it is at

Answer:
The number of turns of the solenoid is 3536 turns
Explanation:
Given;
magnetic field of the solenoid, B = 0.1 T
current in the solenoid, I = 1.8 A
length of the solenoid, L = 8cm = 0.08m
The magnetic field near the center of the solenoid is given by;
B = μ₀nI
Where;
μ₀ is permeability of free space = 4π x 10⁻⁷ m/A
n is number of turns per length
I is the current in the coil
The number of turns per length is calculated as;
n = B / μ₀I
n = (0.1 ) / (4π x 10⁻⁷ x 1.8)
n = 44203.95 turns/m
The number of turns is calculated as;
N = nL
N = (44203.95)(0.08)
N = 3536 turns
Therefore, the number of turns of the solenoid is 3536 turns
Answer:
The average force has a magnitude 6524 N due north.
Explanation:
The average net force F = ma where m = mass of car = 1400 kg and a = acceleration.
a = (v - u)/t where u = initial velocity of car = 0 m/s (since it starts from rest)
v = final velocity of car = 27 m/s due north and t = time of motion = 5.8 s
a = (27 m/s - 0 m/s)/5.8 s = 27 m/s ÷ 5.8 s = 4.66 m/s
Since the direction of the velocity change is the direction of the acceleration, the acceleration is 4.66 m/s due north.
The average force, F = ma = 1400 kg × 4.66 m/s = 6524 N
Since the acceleration is due north, the average force takes the direction of the acceleration.
So the direction of the average force is due north
The average force has a magnitude 6524 N due north.