Explanation:
(b) A uniform beam 150cm long weighs 3.5kg and
supported on knife-edges at its ends. The beam
supports a weight 7kg at a distance 30cm from
one end. Find the reactions of the supports.
Answer:
407 steps
Explanation:
From the question,
P = mgh/t........... Equation 1
Where P = power, m = mass, g = acceleration due to gravity, h = height, t = time.
Make h the subject of the equation
h = Pt/mg............. Equation 2
Given: P = 746 W, t = 1 minute = 60 seconds, m = 70 kg.
Constant: g = 9.8 m/s²
Substitute into equation 2
h = 746(60)/(70×9.8)
h = 44760/686
h = 65.25 m
h = 6525 cm
number of steps = 6525/16
number of steps = 407 steps
Answer:
B) Friction
Explanation:
The main source of error is the omission of the effect from friction between block and incline, which is directly proportional to the mass of the block. The force of gravity is constant. The friction force dissipates part of the gravitational potential energy, generating a final speed less than calculated under the consideration of a conservative system. Air resistance is neglected at low speeds like this case.
Answer:
F = Gm1m2/r^2 where G = 6.67x10^-11, m1 =1300, m2 = 7800, r = 0.23m
F = 6.67x10^-11 *1300*7800/(0.23)^2 = 0.0127852N
Explanation:
Answer : The correct option is, (d) 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of copper = 
= specific heat of water = 
= mass of copper = 120 g
= mass of water = 300 g
= final temperature of mixture = 
= initial temperature of copper = ?
= initial temperature of water = 
Now put all the given values in the above formula, we get:
Therefore, the temperature of the kiln was,
