Answer:
t = 4.17 [s]
Explanation:
We know that work is defined as the product of force by distance.
W = F*d
where:
F = force [N] (units of Newtons)
d = distance = 6.34 x 10⁴ [mm] = 63.4 [m]
In order to find the force, we must determine the weight of the box, the weight can be determined by means of the product of mass by gravitational acceleration.
w = m*g
where:
m = mass = 1.47 x 10⁴ [g] = 14.7 [kg]
g = gravity acceleration = 9.81 [m/s²]
w = 14.7*9.81
w = 144.2 [N]
Therefore the work can be calculated.
W = w*d
W = 144.2*63.4
W = 9142.72 [J] (units of Joules)
Power is now defined in physics as the relationship of work at a given time
P = W/t
where:
P = power = 2190 [W]
t = time [s]
Now clearing t, we have.
t = W/P
t = 9142.72/2190
t = 4.17 [s]
Answer: machine's efficiency = 82.2%
Explanation:
Efficiency of a machine is the capability of a machine to convert input to output without waste.
It can be expressed as
Efficiency = output/ input × 100%
Output = 7,023N
Imput = 8,542N
Efficiency = 7,023N/8,542N × 100%
Efficiency = 82.2%
To calculate the specific heat capacity of an object or substance, we can use the formula
c = E / m△T
Where
c as the specific heat capacity,
E as the energy applied (assume no heat loss to surroundings),
m as mass and
△T as the energy change.
Now just substitute the numbers given into the equation.
c = 2000 / 2 x 5
c = 2000/ 10
c = 200
Therefore we can conclude that the specific heat capacity of the block is 200 Jkg^-1°C^-1
