Answer:
always same
Explanation:
velocity and speed are same upto some extend but velocity is vector while speed is scalar quantity
Answer:
b) 68,9 km/h a) picture
Explanation:
In this problem, since velocity is expressed in km/h and time in minutes, we have to convert either time to hours or velocity to km/min. It is easier to use hours.
Using this formula we pass time to hours:

Now we can plot speed vs time (image 1). The problem says that the driver uses constant speed, so all lines have to be horizontal.
Using the values of the speed we calculate the distance in each interval

Using these values and the fact that she was having lunch in the third one (therefore stayed in the same position), we plot position vs time, using initial position zero (image 2, distance is in km, not meters).
Finally, we compute the average speed with the distance over time:

Answer:
a. 60.5 kg
Explanation:
Given data,
The maximum water a boat can displace is, 60.5 ml
According to the principle of buoyancy, the weight of the floating body is equal to the weight of the liquid displaced.
Under standard temperature and pressure, a unit mass of water equals one liter.
If a boat can displace a maximum of 60.5 ml of water, then it can hold a mass of a maximum of 60.5 kg of mass.
Answer:
The gazelles top speed is 27.3 m/s.
Explanation:
Given that,
Acceleration = 4.2 m/s²
Time = 6.5 s
Suppose we need to find the gazelles top speed
The speed is equal to the product of acceleration and time.
We need to calculate the gazelles top speed
Using formula of speed

Where, v = speed
a = acceleration
t = time
Put the value into the formula


Hence, The gazelles top speed is 27.3 m/s.