Answer:
13.18 m/s
Explanation:
Let the velocity of sports utility car is
-u as it is moving in opposite direction.
mc = 1200 kg, uc = 31.1 m/s
ms = 2830 kg, us = - u = ?
Using conservation of momentum
mc × uc + ms × us = 0
1200 × 31.1 - 2830 × u = 0
u = 13.18 m/s
Galileo successfully demonstrated that the balls took the same amount of time to reach the ground.
Choice B
Sometimes it just picks for you
Answer:
* energy is proportional to masses. in a graph it would look like a line
* kinetic energy varies with the square of the velocity, In a graph it gives rise to a quadratic curve
Explanation:
Kinetic energy is defined by
K = ½ m v²
when analyzing this expression we can see:
* energy is proportional to masses. Therefore, doubling the mass doubles the kinetic energy and if the mass rises 4 times the energy rises 4 times, that is, they are directly proportional, in a graph it would look like a line
* kinetic energy varies with the square of the velocity. Therefore by doubling the speed the energy goes up 4 times. In a graph it gives rise to a quadratic curve
<h2>When two object P and Q are supplied with the same quantity of heat, the temperature change in P is observed to be twice that of Q. The mass of P is half that of Q. The ratio of the specific heat capacity of P to Q</h2>
Explanation:
Specific heat capacity
It is defined as amount of heat required to raise the temperature of a substance by one degree celsius .
It is given as :
Heat absorbed = mass of substance x specific heat capacity x rise in temperature
or ,
Q= m x c x t
In above question , it is given :
For Q
mass of Q = m
Temperature changed =T₂/2
Heat supplied = x
Q= mc t
or
X=m x C₁ X T₁
or, X =m x C₁ x T₂/2
or, C₁=X x 2 /m x T₂ (equation 1 )
For another quantity : P
mass of P =m/2
Temperature= T₂
Heat supplied is same that is : X
so, X= m/2 x C₂ x T₂
or, C₂=2X/m. T₂ (equation 2 )
Now taking ratio of C₂ to c₁, We have
C₂/C₁= 2X /m.T₂ /2X /m.T₂
so, C₂/C₁= 1/1
so, the ratio is 1: 1
