Answer:
C. 441 N
Explanation:
Gravitational force between two objects can by calculated by the formula
= G m₁m₂ / r² , m₁ and m₂ are masses at distance r
= ( 6.67 x 10⁻¹¹ x 45 x 5.98 x 10²⁴) / ( 6.38 x 10⁶ )²
= 44.09 x 10
= 440.9 N
= 441 N .
Answer:
Final velocity v = 8.944 m/sec
Explanation:
We have given distance S = 40 meters
Time t = 10 sec
As it starts from rest so initial velocity u = 0
From second equation of motion 
Now from first equation of motion 
, here v is final velocity, u is initial velocity, a is acceleration and t is time
So 
In general, the quantity of heat energy, Q, required to raise a mass m kg of a substance with a specific heat capacity of <span>c </span>J/(kg °C), from temperature t1 °C to t2 °C is given by:
<span>Q </span>= <span>mc(t</span><span>2 </span><span>– t</span>1<span>) joules</span>
<span>So:</span>
(t2-t1) =Q / mc
<span>As we know:
Q = 500 J </span>
<span>m = 0.4 kg</span>
<span>c = 4180 J/Kg </span>°c
<span>We can take t1 to be 0</span>°c
t2 - 0 = 500 / ( 0.4 * 4180 )
t2 - 0 = 0.30°c
Answer:
a) -41.1 Joule
b) 108.38 Kelvin
Explanation:
Pressure = P = 290 Pa
Initial volume of gas = V₁ = 0.62 m³
Final volume of gas = V₂ = 0.21 m³
Initial temperature of gas = T₁ = 320 K
Heat loss = Q = -160 J
Work done = PΔV
⇒Work done = 290×(0.21-0.62)
⇒Work done = -118.9 J
a) Change in internal energy = Heat - Work
ΔU = -160 -(-118.9)
⇒ΔU = -41.1 J
∴ Change in internal energy is -41.1 J
b) V₁/V₂ = T₁/T₂
⇒T₂ = T₁V₂/V₁
⇒T₂ = 320×0.21/0.62
⇒T₂ = 108.38 K
∴ Final temperature of the gas is 108.38 Kelvin
Answer:
(b) B
Explanation:
The direction of force on a current carrying wire in a magnetic field can be found using the right hand rule, which states that-"stretch the thumb in the direction of the current, and point the fingers in the direction of magnetic field. The direction of palm will then give the direction of force on the wire
On wire B the forces due to A and C act in the same direction and so strengthen each other. they get added up because the forces act in the same direction.
on wires A and C the forces (due to B and C and A and B
respectively) act in opposite directions and therefore tend to cancel out.
