Known :
l = 7 cm
w = 4 cm
Asked :
h = ...?
Answer :
V = B triangle × h (long)
35 = ½ × 4 × h × 7
35 = ½ × 28 × h
35 = 14 h
h = 35 ÷ 14
h = 2,5 cm
Sorry if I am wrong, I only study
Answer:
An object at rest stays at rest as long as unbalanced forces act on it.
Explanation:
Inertia can be defined as the tendency of an object or a body to continue in its state of motion or remain at rest unless acted upon by an external force.
In physics, Sir Isaac Newton's First Law of Motion is known as Law of Inertia and it states that, an object or a physical body in motion will continue in its state of motion at continuous velocity (the same speed and direction) or, if at rest, will remain at rest unless acted upon by an external force.
The inertia of a physical object such as a truck is greatly dependent or influenced by its mass; the higher the quantity of matter in a truck, the greater will be its tendency to continuously remain at rest.
Hence, the situation which is contrary to Newton’s first law of motion is that, an object at rest stays at rest as long as unbalanced forces act on it.
According to Newton’s first law of motion, an object at rest stays at rest as long as unbalanced forces do not act on it.
Answer:

Explanation:
14 lb force is required to stretch the spring by 4 inch distance
So we have



stretch in the spring is given as

now we will have



Now we need to find the work to stretch it by x = 10 in = 0.254 m
so we have



Answer:
Explanation:
According to Boyle's law for constant temperature of gas Pressure is inversely proportional to the volume of gas.



if Pressure is tripled then


Volume becomes one-third of original volume
Answer:
650.65 K or 377.5°C
Explanation:
Area = A = 10 m²
Thickness of wall = L = 2.5 cm = 2.5×10⁻² m
Inner surface temperature of wall =
= 415°C = 688.15 K
Outer surface temperature of wall = 
Heat loss through the wall = 3 kW = 3×10³ W
Thermal conductivity of wall = k = 0.2 W/m K
Assumptions made here as follows
- There is not heat generation in the wall itself
- The heat conduction is one dimensional
- Heat flow follows steady state
- The material has same properties in all directions i.e., it is homogeneous.
Considering the above assumptions we use the following formula

∴ The temperature of the outer surface of the wall is 650.65 K or 377.5°C