Answer:c
Explanation:
In Physics we follow the sign convention i.e. work done by the system is considered as positive i.e. work is being done by system on the surrounding and vice-versa.
For heat :Heat added to the system is considered as Positive while heat loss to surrounding is considered as negative.
thus doing work on the surrounding(work done by system) w=+
Losing heat to the surrounding q=-
Answer:
0.2 J
Explanation:
The pendulum forms a right triangle, with hypotenuse of 50 cm and base of 30 cm. The height of this triangle can be found with Pythagorean theorem:
c² = a² + b²
(50 cm)² = a² + (30 cm)²
a = 40 cm
The height of the triangle is 40 cm. The height of the pendulum when it is at the bottom is 50 cm. So the end of the pendulum is lifted by 10 cm. Assuming the mass is concentrated at the end of the pendulum, the potential energy is:
PE = mgh
PE = (0.200 kg) (9.8 N/kg) (0.10 m)
PE = 0.196 J
Rounding to one significant figure, the potential energy is 0.2 J.
Answer:
14.1 kg
Explanation:
Given:
Length=7.00inches
Width=3.63 inches
Height=1.75 inches
density = 19,300 kg/m3.
We can convert the given parameters to metre for unit consistency
But we know 1 inches= 0.0254 metre
✓Then Length l=7.00inches
=7×0.0254 metre=0.1778m
✓Width w =3.63 inches
==3.63 ×0.0254 metre=0.092m
✓Height h =1.75 inches
=1.75 ×0.0254 metre=0.0445 m
But Mass= density × volume
Volume= Length× width×height
Mass= density× Length× width×height
= 19300kg/m³×0.1778×0.0922×0.0445
=14.1 kg
Therefore, the mass of the gold bar is 14.1 kg
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Answer:
0 degrees
Explanation:
Let 
are two forces. The resultant of two forces acting on the same point is given by :
Where 
is the angle between two forces
When 
i.e. when two forces are parallel to each other,
When 
i.e. when two forces are parallel to each other,
When 
i.e. when two forces are parallel to each other,
It is clear that the resultant of two forces acting on the same point simultaneously will be the greatest when the angle between them is 0 degrees. Hence, this is the required solution.
