Answer:
the initial velocity of the ball is 104.67 m/s.
Explanation:
Given;
angle of projection, θ = 60⁰
time of flight, T = 18.5 s
let the initial velocity of the ball, = u
The time of flight is given as;

Therefore, the initial velocity of the ball is 104.67 m/s.
The force of friction is 78.4 N
What is force of friction?
Frictional force is the force created when two surfaces come into contact and slide against each other. it is given by the equation:
μ * 
where,
= force of friction
μ = coefficient of friction
= normal force
Given,
μ 
We know,


Subsituing the values in equation:
μ * 

The force of friction is 78.4 N.
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Answer:
Explanation:
a )
current in the wire = potential diff / resistance
= 23 / (15 x 10⁻³ )
= 1.533 x 10³ A .
b )
For resistance of a wire , the formula is
R = ρ L / S where ρ is specific resistance , L is length and S is cross sectional area of wire
putting the given values
15 x 10⁻³ = 4ρ / π x .003²
ρ = 106 x 10⁻⁹ ohm. m
= 10.6 x 10⁻⁸ ohm m
The metal wire appears to be platinum .
Answer:
The spring constant is 215.6 N/m.
Explanation:
Given that,
Distance = 39 cm
Compresses length = 29 cm
Mass = 2.2 kg
We need to calculate the distance
Using formula of distance

Put the value into the formula
We need to calculate the spring constant
Using formula of restoring force


Where, F = force
x = distance
Put the value into the formula


Hence, The spring constant is 215.6 N/m.