Hey there,
Your correct answer would be 30kg.
450 = m × 15 or also 450/15=m.
Hope this helps.
~Jurgen
Answer: Option B) 1038J
Explanation:
Given that
Mass of person (m) = 83kg
kinetic energy (KE) = ?
Speed of elevator (v) = 5m/s
Kinetic energy is the energy possessed by a moving object. It is measured in joules, and depends on the mass (m) of the object and the speed (v) by which it moves
i.e K.E = 1/2mv²
KE = 1/2 x 83kg x (5m/s)²
KE = 0.5 x 83 x 25
KE = 1037.5J (Round the kinetic energy to the nearest whole number as 1038J)
Thus, the kinetic energy of the person is 1038 Joules
Answer:
K = 2 10⁻⁸ J
Explanation:
Let's solve this exercise in parts, we start by finding the charge on each plate of the capacitor
C = Q / ΔV
C = ε₀ A / d
ε₀ A / d = Q / ΔV
Q = ε₀ A ΔV / d (1)
indicate the potential difference ΔV₁ = 12 V, the distance between the plates d₁ = 3 mm = 0.003 m,
as the power supply is disconnected and the capacitor is ideal the charge remains constant
in the second part we separate the plates at d₂ = 5 mm = 0.005 m, using equation 1
ΔV₂ =
we substitute the equation for Q
ΔV₂ =
ΔV₂ =
in the third part we use the concepts of energy
starting point. Test charge near positive plate
Em₀ = U = q ΔV₂
final point. Test charge near negative plate
Em_f = K
energy is conserved
Em₀ = Em_f
q ΔV₂ = K
K = q ΔV₁
we calculate
K = 1 10⁻⁹ 12 0.005/0.003
K = 2 10⁻⁸ J
Answer:
67000N
Explanation:
We solve for the acceleration using the the 3rd constant-acceleration equation.
(Vx)f² = (Vx)i² + 2ax∆x
We have the displacement to be
∆x = Xf - Xi = 940m
Vx = 70m/s
The acceleration = (70m/s)²/2(940m)
= 4900/1880
= 2.61m/s²
From isaac newton's second law,
51000kg x 2.61m/s²
= 133,000N
The engines thrust is half of this value
Therefore thrust = 67000N or 67kN
Step by step solution :
standard deviation is given by :
where, is standard deviation
is mean of given data
n is number of observations
From the above data,
Now, if , then
If , then
if , then
If , then
If , then
so,
No, Joe's value does not agree with the accepted value of 25.9 seconds. This shows a lots of errors.