The astronaut's weight on the Earth's surface can be determined from
<span>F = m g = 579.2 N subsituting </span><span> mass equal to 59.1 kg and acceleration due to gravity equal to 9.8 m/s². When the variables are mass of the earth and the radius of the earth, </span>F = k m / r². Thus, doubling the mass of the earth would double his weight and doubling the radius would decrease the original weight by 1/4. Hence, <span>579.2 N* 2* 1/4 equal to 290 N. Answer is B.</span>
Answer:
so change in primary current is 1.620 A
Explanation:
Given data
current I =6.0-mA = 6 × 10^(-3) A
resistance R = 12 Ω
mutual inductance M = 3.2 mH = 3.2 × 10^(-3) H
dt = 72-ms = 72 × 10^-(3) s
to find out
change in the primary current
solution
we know that
Electric and magnetic fields in secondary coil = mutual inductance × change in primary current / dt ............1
and we know also that Electric and magnetic fields in secondary coil = resistance × current
so = 6 × 10^(-3) × 12 = 72 × 10^(-3) volts
so that we say
change in primary current from equation 1
change in primary current = Electric and magnetic fields in secondary coil × dt / mutual inductance
change in primary current = 72 × 10^(-3) × 72 × 10^(-3) / 3.2 × 10^(-3)
change in primary current = 1.620
so change in primary current is 1.620 A
Answer:
3.4 x 10⁴ m/s
Explanation:
Consider the circular motion of the electron
B = magnetic field = 80 x 10⁻⁶ T
m = mass of electron = 9.1 x 10⁻³¹ kg
v = radial speed
r = radius of circular path = 2 mm = 0.002 m
q = magnitude of charge on electron = 1.6 x 10⁻¹⁹ C
For the circular motion of electron
qBr = mv
(1.6 x 10⁻¹⁹) (80 x 10⁻⁶) (0.002) = (9.1 x 10⁻³¹) v
v = 2.8 x 10⁴ m/s
Consider the linear motion of the electron :
v' = linear speed
x = horizontal distance traveled = 9 mm = 0.009 m
t = time taken = 
= 
= 4.5 x 10⁻⁷ sec
using the equation
x = v' t
0.009 = v' (4.5 x 10⁻⁷)
v' = 20000 m/s
v' = 2 x 10⁴ m/s
Speed is given as
V = sqrt(v² + v'²)
V = sqrt((2.8 x 10⁴)² + (2 x 10⁴)²)
v = 3.4 x 10⁴ m/s
Whenever we represent forces using vectors, we ensure that the vector begins at the point of force exertion. In the case of weight, the point of exertion of the force is known as the center of gravity, which is the point through which the weight of an object can be said to act. Therefore, the downward arrow representing the weight would begin at the center of gravity of the object.
