Answer:
As follows,
Explanation:
KE=1/2mv^2
In 1st question,
KE=1/2mv^2=1/2*0.05*12=0.3 J [50g=0.05 kg]
In 2nd question,
KE=1/2mv^2
6.8=1/2*0.046*v^2
v=sqrt(6.8/0.023)
v=17.19
In 3rd question,
KE=1/2mv^2
63/392=m
m=0.16kg=160g
For 4th,
a.
1st case,
KE=1/2mv^2=1/2*28*2.4^2=80.64
2nd case,
KE=1/2mv^2=1/2*28*3.7^2=191.66
Change in KE=191.66-80.64=11.02
b.Speed/velocity gained
The correct answer is 40.5 Newtons just finished the quiz and 36.5 was incorrect.
Answer:

Explanation:
The torque of a force is given by:

where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation of the system
is the angle between the direction of the force and d
In this problem, we have:
, the force
, the distance of application of the force from the centre (0,0)
, the angle between the direction of the force and a
Therefore, the torque is

Answer:
Explanation:
The electric field outside the sphere is given as,
E = k Q /r²
here Q = n x 1.6 x 10⁻¹⁹ C
where n is the number of electons
if the dimeter of sphere d= 25 cm= 0.25 m
then the radius r = 0.125 m
we get
n= E r²/ k x 1.6 x 10⁻¹⁹ C
n = 1350N/C x (0.125m)² / (8.99 x 10⁹ N m²/C² x 1.6 x 10⁻¹⁹ C)
n = 14664731646
Answer:
final position = 325 m
Explanation:
distance covered in 1 second = speed x time
= 355 m/s x 1 s
= 355 m
∴ final position = initial position + distance covered
= - 30 m + 355 m
= 325 m