Answer:
Final speed of the car, v = 24.49 m/s
Explanation:
It is given that,
Initial velocity of the car, u = 0
Acceleration, 
Time taken, t = 7.9 s
We need to find the final velocity of the car. Let it is given by v. It can be calculated using first equation of motion as :

v = 24.49 m/s
So, the final speed of the car is 24.49 m/s. Hence, this is the required solution.
Answer:
The work done by gravity is 784 J.
Explanation:
Given:
Mass of the block is, 
Height to which it is raised is, 
Acceleration due to gravity is, 
Now, work done by gravity is equal to the product of force of gravity and the distance moved in the direction of gravity. So,

Force of gravity is given as the product of mass and acceleration due to gravity.
. Now,

Therefore, the work done by gravity is 784 J.
Answer: 117 kPa
Explanation:
For the liquid at depth 3 m, the gauge pressure is equal to = P₁=39 kPa
For the liquid at depth 9m, the gauge pressure is equal to= P₂
Now we are given the condition that the liquid is same. That must imply that the density must be same throughout the depth.
So, For finding gauge pressure we have formula P= ρ * g * h
Also gravity also remains same for both liquids
So taking ratio of their respective pressures we have
= 
So
= 
Or P₂= 39 * 3 = 117 kPa
B. False
Endothermic reactions absorb heat.
Answer:
t= 27.38 mins [this the time taken by the enzyme to hydrolyse 80% of the fat present]
Explanation:given values
Half life of lipase t_1/2 = 8 min x 60s/min = 480 s
Rate constant for first order reaction
k_d = 0.6932/480 = 1.44 x 10^-3 s-1
Initial fat concentration S_0 = 45 mol/m3 = 45 mmol/L
rate of hydrolysis Vm0 = 0.07 mmol/L/s
Conversion X = 0.80
Final concentration S = S_0(1-X) = 45 (1-0.80) = 9 mol/m3
K_m = 5mmol/L
time take is given by
![t= -\frac{1}{K_d}ln[1-\frac{K_d}{V_m_0}(k_mln\frac{s_0}{s}+(s_0-s))]](https://tex.z-dn.net/?f=t%3D%20-%5Cfrac%7B1%7D%7BK_d%7Dln%5B1-%5Cfrac%7BK_d%7D%7BV_m_0%7D%28k_mln%5Cfrac%7Bs_0%7D%7Bs%7D%2B%28s_0-s%29%29%5D)
all values are given and putting these value we get
t=1642.83 secs
which is equal to
t= 27.38 mins [this the time taken by the enzyme to hydrolyse 80% of the fat present]