# A sailboat is traveling to the right when a gust of wind causes the boat to accelerate leftward at 2.5​​​​m​​/s2 for 4s. After the wind stops, the sailboat is traveling to the left with a velocity of 3.0​m/s. Assuming the acceleration from the wind is constant, what was the initial velocity of the sailboat before the gust of wind? Answer using a coordinate system where rightward is positive.

Answer: Taking right movement to be positive means leftward movement is negative.
Hence we have a deceleration of

Using this 'suvat' equation

we can determine the initial velocity

Hence the initial velocity is 13.0 meters per seconds

Explanation :

Let rightward direction is considered as positive and leftward direction is considered as negative.

Given that,

Acceleration of the boat, ( in left )

Time taken,

Final velocity of the boat,

We have to find initial velocity (u) of the sailboat.

Using first equation of motion :

So, initially the boat is moving with a speed of 13 m/s in leftwards direction.

Hence, this is the required solution.

## Related Questions

What average net force is required to stop an 8500 kg truck in 10 s if it’s initially traveling at 20 m/s?

We have: F = m × v/t
Here, m = 8500 Kg
v = 20 m/s
t = 10 s

Substitute their values into the expression,
F = 8500 × 20/10
F = 8500 × 2
F = 17000 N

In short, final answer would be 17000 N

Hope this helps!!

Suppose 1 gold bar is 6 cm long, 2 cm high, and 3 cm wide. How many whole gold bars will you be able to fit in a vault with a volume of 500 cm3?

We are given the dimensions of a gold bar and is asked how many of these gold bars are able to fit into a 500 cm3 volume. we first calculate the volume of a gold bar that is 6 cm x 2 cm x 3 cm equal to 36 cm3. We divide 500 cm3 by 36 cm3 per gold bar equal to approx. 13 bars

Answer : The number of gold bar able to fit in a vault with a volume of will be 14.

Explanation :

First we have to calculate the volume of 1 gold bar.

Given :

Length of gold bar = 6 cm

Width of gold bar = 3 cm

Height of gold bar = 2 cm

Formula used :

Volume = Length × Width × Height

Volume = 6cm × 3cm × 2cm

Volume =

Thus, the volume of 1 gold bar is

Now we have to calculate the number of gold bar will be able to fit in a vault with a volume of

Therefore, the number of gold bar able to fit in a vault with a volume of will be 14.

The position vector r describes the path of an object moving in the xy-plane. position vector point r(t) = ti + (ât2 + 7)j (1, 6) (a) find the velocity vector, speed, and acceleration vector of the object.

We can decompose the problem on x- and y-axis.

The position vector decomposed is:

The velocity vector can be found computing the derivative of r on both axes:

So, the velocity vector is
r' = 1i+2atj

The speed (the magnitude of the velocity vector) is

Finally we can write the acceleraion vector by performing derivation on the velocity vector:

and so
r''=2a j

Speed is the rate at which an object moves relative to its reference point. Average speed is the total distance divided by the total time. We use average speed because the speed of an object may vary over time. Common measures of speed include miles per hour, meters per second or kilometers per minute. If you drive at a speed limit of 65 miles per hour, it means that in one hour you will have traveled 65 miles from the reference point of where you began. Because the speed at which an object travels varies over time,
A
it is impossible to calculate any type of speed measurement.
B
distance is considered the more important measurement.
C
average speed is used, which is total distance divided by total time.
D
time is considered the more important measurement.