Answer:
E = 62.72 J
Explanation:
Given that,
The mass of a ball, m = 4 kg
The teacher raised the lawn bowling ball to a height of 1.6 meters before
they released it.
We need to find the gravitational potential energy of the ball.
We know that,
E = mgh
Where
g is acceleration due to gravity
So,
E = 4 kg × 9.8 m/s² × 1.6 m
E = 62.72 J
So, the gravitational potential energy of the ball is equal to 62.72 J.
Answer:
a = = 37.2V
b = 13.39MJ
Explanation:
Given that
L = 170 × 10³
r = d/2
= 10cm / 2 = 5 cm
current I = 100A
we are to find the potential drop across the cable
so, we can use ohm’s law
V = IR = I (ρL/A)
ρ = resistivity of the copper
= 1.72 × 10⁻⁸ Ω.m
A = πr²
V = I(ρL/πr²)
= 100 (( 1.72 × 10⁻⁸ * 170 × 10³) / ( π * 0.05²))
= 37.2V
(b)
Energy (loss) = Pt
Enery (loss) = IVt
3600s per hour
= (100A)(37.2V)(3600s)
= 13.39MJ
Answer:
26.83 N.
Explanation:
If the angle between two vector is 90°, to get the resultant, we use Pythagoras theorem.
a² = b²+c²......................... Equation 1
Where a = R = Resultant, b = 12 N, c = 24 N.
Substitute these values into equation 1
R² = 12²+24²
R² = 144+576
R² = 720
√R² = √720
R = 26.83 N.
Hence, the result of the two force is 26.83 N.
Rate of change of momentum = impact force
(m*v-m*u)/t = F
4000*20/t = 80000 (note: v is zero as it stopped)
<span>soo, t = 1 sec</span>
