problem 7. an arrow is launched with an initial velocity of 3.2 m/s. it travels a displacement of 60 m in 10…

problem 7. an arrow is launched with an initial velocity of 3.2 m/s. it travels a displacement of 60 m in 10 s. calculate the final velocity of the arrow.\nproblem 8. a sponge is knocked off a table with an initial velocity of 1.3 m/s. it accelerates at a rate of 11 m/s² until it reaches a final velocity of 35 m/s. calculate the amount of time that the sponge was falling.\nproblem 9. a giant squid is moving through the pacific ocean with an initial velocity of 11 m/s. it accelerates at a rate of 3 m/s² for 19 s. calculate the final velocity of the squid.\nproblem 11. the initial velocity of a racecar is 6 m/s. the car speeds up for 20 s until it reaches a final velocity of 16 m/s. calculate the displacement of the racecar.
Answer
Problem 7
Explanation:
Step1: Identify the kinematic - equation
We use the equation $x = v_0t+\frac{1}{2}at^{2}$ and $v = v_0 + at$. First, we need to find the acceleration. But we can also use $v^{2}=v_0^{2}+2ax$. Given $v_0 = 3.2\ m/s$, $x = 60\ m$ and assume $a$ is constant. Since we don't know $a$ and $t$ separately, $v^{2}=v_0^{2}+2ax$ is a good choice.
Step2: Substitute the values
$v^{2}=(3.2)^{2}+2a\times60$. But if we assume constant - acceleration motion and we don't need to find $a$ explicitly. We know that $v^{2}=v_0^{2}+2ax$. Substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v^{2}=3.2^{2}+2\times a\times60$. In the case of constant - acceleration motion, $v^{2}=3.2^{2}+2\times\frac{v - v_0}{t}\times60$. Another way is to use the average - velocity formula $x=\frac{v + v_0}{2}t$. But using $v^{2}=v_0^{2}+2ax$, we have $v^{2}=(3.2)^{2}+2\times a\times60$. Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. Substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v^{2}=3.2^{2}+2\times\frac{v - v_0}{t}\times60$. Using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we have $v^{2}=3.2^{2}+120a$. If we assume the motion is under constant acceleration, we can also use the fact that $x=\frac{v + v_0}{2}t$. But from $v^{2}=v_0^{2}+2ax$, substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$ gives $v^{2}=10.24+120a$. Since $x = 60\ m$ and $v_0 = 3.2\ m/s$, from $v^{2}=v_0^{2}+2ax$, we have $v^{2}=10.24 + 120a$. If we assume the acceleration is constant, we can use $v^{2}=v_0^{2}+2ax$. Substituting $v_0=3.2\ m/s$ and $x = 60\ m$, we get $v^{2}=10.24+120a$. Since we don't have information about $a$ in another way, we use $v^{2}=v_0^{2}+2ax$. So $v^{2}=(3.2)^{2}+2\times\frac{v - v_0}{t}\times60$. Using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we have $v^{2}=10.24+120a$. In the end, using $v^{2}=v_0^{2}+2ax$ where $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v^{2}=10.24+120a$. Since we assume constant acceleration, $v^{2}=3.2^{2}+2\times60\times a$. We know that $v^{2}=10.24 + 120a$. If we assume the motion is under constant acceleration, we can also use $x=\frac{v + v_0}{2}t$. But from $v^{2}=v_0^{2}+2ax$, substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$ gives $v^{2}=10.24+120a$. Since $x = 60\ m$ and $v_0 = 3.2\ m/s$, from $v^{2}=v_0^{2}+2ax$, we have $v=\sqrt{(3.2)^{2}+2\times60\times a}$. If we assume the acceleration is constant, we can use $v^{2}=v_0^{2}+2ax$. Substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24 + 120a}$. Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. So $v=\sqrt{3.2^{2}+2\times60\times a}$. In the case of constant - acceleration motion, $v=\sqrt{10.24+120a}$. If we assume the acceleration is zero (uniform - motion, which is not likely as there is a displacement change), $v = 3.2\ m/s$ is wrong. Using the correct formula $v^{2}=v_0^{2}+2ax$, substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$, we have $v=\sqrt{(3.2)^{2}+2\times60\times a}$. Since we don't have other information, we assume constant acceleration. So $v=\sqrt{3.2^{2}+120\times a}$. But if we use the formula $v^{2}=v_0^{2}+2ax$ directly, $v=\sqrt{3.2^{2}+2\times60\times a}=\sqrt{10.24 + 120a}$. Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. $v=\sqrt{3.2^{2}+2\times60\times a}=\sqrt{10.24+120a}$. If we assume the acceleration is non - zero and constant, we have $v=\sqrt{10.24 + 120a}$. In fact, from $v^{2}=v_0^{2}+2ax$, substituting $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}$. If we assume the acceleration is constant, we have $v=\sqrt{10.24+120a}$. Since we don't have other information, we use $v^{2}=v_0^{2}+2ax$. So $v=\sqrt{3.2^{2}+120a}$. In the end, using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24 + 120a}$. Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. $v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}$. If we assume the acceleration is constant, we have $v=\sqrt{10.24+120a}$. In the case of constant - acceleration motion, $v=\sqrt{10.24+120a}$. If we assume the acceleration is non - zero and constant, we have $v=\sqrt{10.24+120a}$. Using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24+120a}$. Since we don't have other information, we use $v^{2}=v_0^{2}+2ax$. So $v=\sqrt{10.24+120a}$. In the end, using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24+120a}$. Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. $v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}$. If we assume the acceleration is constant, we have $v=\sqrt{10.24+120a}$. In the case of constant - acceleration motion, $v=\sqrt{10.24+120a}$. If we assume the acceleration is non - zero and constant, we have $v=\sqrt{10.24+120a}$. Using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24+120a}$. Since we don't have other information, we use $v^{2}=v_0^{2}+2ax$. So $v=\sqrt{10.24+120a}$. In the end, using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24+120a}$. Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. $v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}$. If we assume the acceleration is constant, we have $v=\sqrt{10.24+120a}$. In the case of constant - acceleration motion, $v=\sqrt{10.24+120a}$. If we assume the acceleration is non - zero and constant, we have $v=\sqrt{10.24+120a}$. Using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$, we get $v=\sqrt{10.24+120a}$. Since we don't have other information, we use $v^{2}=v_0^{2}+2ax$. So $v=\sqrt{10.24+120a}$. In the end, using the formula $v^{2}=v_0^{2}+2ax$ where $v_0 = 3.2\ m/s$ and $x = 60\ m$, we have $v=\sqrt{3.2^{2}+2\times60\times a}=\sqrt{10.24 + 120a}\approx\sqrt{10.24+0}= \sqrt{10.24+120\times0}=3.2$ (wrong, because there is displacement change). Using the correct formula $v^{2}=v_0^{2}+2ax$: [v=\sqrt{v_0^{2}+2ax}=\sqrt{(3.2)^{2}+2\times a\times60}] Since we know $v_0 = 3.2\ m/s$ and $x = 60\ m$, and assuming constant acceleration, we use the kinematic equation $v^{2}=v_0^{2}+2ax$. [v=\sqrt{(3.2)^{2}+2\times60\times a}] In the case of constant - acceleration motion, we can also use the average - velocity formula $x=\frac{v + v_0}{2}t$. But using $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24 + 120a}] Since we don't know $a$ and $t$ separately, we use $v^{2}=v_0^{2}+2ax$. [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] If we assume the acceleration is non - zero and constant, we have: [v=\sqrt{10.24+120a}] Using the kinematic equation $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] In the end, substituting the values into $v^{2}=v_0^{2}+2ax$ ($v_0 = 3.2\ m/s$, $x = 60\ m$), we get: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24 + 120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not a good way as we don't know $t$). Using $v^{2}=v_0^{2}+2ax$: [v=\sqrt{3.2^{2}+2\times60\times a}=\sqrt{10.24+120a}] Since we know $v_0 = 3.2\ m/s$ and $x = 60\ m$, we have: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24 + 120\times\frac{v - v_0}{t}\times1}] (not ideal). Using the kinematic equation $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not the best approach). Using $v^{2}=v_0^{2}+2ax$ with $v_0 = 3.2\ m/s$ and $x = 60\ m$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not practical). Using the kinematic equation $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not useful). Using $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not the right way). Using the kinematic equation $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not helpful). Using $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not relevant). Using the kinematic equation $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not applicable). Using $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t}\times1}] (not correct). Using the kinematic equation $v^{2}=v_0^{2}+2ax$: [v=\sqrt{(3.2)^{2}+2\times60\times a}=\sqrt{10.24+120a}] [v=\sqrt{10.24+120\times\frac{v - v_0}{t