Answer:
The tension in the rope is 281.60 N.
Explanation:
Given that,
Length = 3.0 m
Weight = 600 N
Distance = 1.0 m
Angle = 60°
Consider half of the ladder,
let tension be T, normal reaction force at ground be F, vertical reaction at top hinge be Y and horizontal reaction force be X.
....(I)
.....(II)
On taking moment about base

Put the value into the formula


....(III)
We need to calculate the force for ladder


We need to calculate the tension in the rope
From equation (3)




Hence, The tension in the rope is 281.60 N.
Answer:
a. The temperature of the copper changed more than the temperature of the water.
Explanation:
Because we're only considering the isolated system cube-water, the heat of the system should be constant, that implies the heat the cube loses is equal the heat the water gains (because by zero law of thermodynamics heat (Q) flows from hot body to cold body until reach thermal equilibrium and T1>T2). So:
(1)
But Q is related with mass (m), specific heat (c) and changes in temperature (
)in the next way:
(2)
Using (2) on (1):



Because we have an equality and 0.385 < 4.186 then
to conserve the equality
The average speed would have to be 260 km/hr due to the driver originally going 30 km/hr too slow the first two laps