b. False
B. walking
C. swimming
D. all of the above
Answer:
D. All of the above
Explanation:
Newton's third law states that:
"when an object A exerts a force on an object B, object B exerts an equal and opposite force on object A. These forces are called action and reaction"
Let's analyze each situation:
A. when hitting a baseball with a bat --> we have two objects (the baseball and the bat), so we have a pair of forces: the action is the force exerted by the baseball on the bat, while the reaction is the force exerted by the bat on the baseball
B. walking --> in this case, the two objects we should consider are the man walking and the road: the action is the force exerted by the feet of the man on the road, while the reaction is the force exerted by the road on the feet of the man, which allows him walking
C. swimming --> in this case, the two objects we should consider are the man swimming and the water around him: the action is the force exerted by the body of the man on the water, while the reaction is the force exerted by the water on the body of the man, which allows him to swim.
So, all the three choices are correct.
The buoyancy of an object depends on its density relative to the density of the fluid it's placed in, typically water in everyday scenarios. When an object is placed in a fluid (like water), it will float if its average density is less than that of the fluid. In other words, if the object is less dense than the fluid, it will float.
In this case, both pieces of wood have the same density of 0.90 grams per milliliter (g/ml), which is less dense than water. Therefore, both the 1-pound piece of wood and the 10-pound piece of wood will float in water.
However, it's important to note that the buoyant force acting on these objects will be the same for a given volume of wood because they have the same density.
The 10-pound piece of wood will displace more water (have a larger volume) to support its weight, while the 1-pound piece of wood will displace less water (have a smaller volume) to support its weight. The 10-pound piece of wood will have more of its volume submerged compared to the 1-pound piece due to the weight difference, but both will float.
Answer:
t = 10.4 s
Explanation:
given,
velocity of the police car = 18 m/s
reaction time of policeman = 0.8 s
acceleration of the policeman to catch up the speeder = 5 m/s²
time taken to catch the speeder be t₁
distance traveled by the police and the speeder will be same
t₁ = 9.6 s
total time taken by the policeman
= reaction time + t₁
= 0.8 + 9.6
t = 10.4 s
Total time taken by the policeman to catch the speeder is 10.4 s
1. B
2. A
3. B
4. A
5. C
6. B
7. B
8. A
Answer: Recall that
Work (W) = - e × ∆V
Where
Charge of electron= 1.6 × 10^ -19 c
And from the question we were given change in potential as = -0.0677V
Work = - (1.6 × 10^-19) × (-0.0677)
Work= 1.0832 × 10^-20J
Therefore the work done by the electric force when a sodium ion (charge = +e) moves from the outside to the inside is 1.0832×10^-20