Question: How fast was the arrow moving before it joined the block?
Answer:
The arrow was moving at 15.9 m/s.
Explanation:
The law of conservation of energy says that the kinetic energy of the arrow must be converted into the potential energy of the block and arrow after it they join:

where
is the mass of the arrow,
is the mass of the block,
of the change in height of the block after the collision, and
is the velocity of the arrow before it hit the block.
Solving for the velocity
, we get:

and we put in the numerical values
,



and simplify to get:

The arrow was moving at 15.9 m/s
Answer:
9.98 × 10⁻⁹ C
Explanation:
mass, m = 1.00 × 10⁻¹¹ kg
Velocity, v = 23.0 m/s
Length of plates D₀ = 1.80 cm = 0.018 m
Magnitude of electric field, E = 8.20 × 10⁴ N/C
drop is to be deflected a distance d = 0.290 mm = 0.290 × 10⁻³ m
density of the ink drop = 1000 kg/m^3
Now,
Time =
or
Time =
or
Time = 6.9 × 10⁻⁴ s
Now, force due to the electric field, F = q × E
where, q is the charge
Also, Force = Mass × acceleration
q × E = 1.00 × 10⁻¹¹ × a
or
a =
Now from the Newton's equation of motion
where,
d is the distance
u is the initial speed
a is the acceleration
t is the time
or
or
q = 9.98 × 10⁻⁹ C
Answer:
the rate of acceleration of the train is 4 m/s²
Explanation:
Given;
initial velocity of the train, u = 10 m/s
change in time of motion, dt = 5 s
final velocity of the train, v = 30 m/s
The rate of acceleration of the train is calculated as;

Therefore, the rate of acceleration of the train is 4 m/s²
Answer
The capacitor should be connected in parallel as parallel connection gives the arithmetic sum of capacitance which will give a corresponding sum of energy while capacitors in series gives the sum of the reciprocal if the individual capacitance
The centripetal force acts upon an object moving in a circle at constant speed. The centripetal force acts perpendicular to the direction of motion , the speed of object will remain constant.