qu.1.topic=<strong>Ch 9</strong>, <font size="-1"><b>Sec 1</b></font> - Linear Momentum@

qu.1.1.mode=Randomized Formula@
qu.1.1.editing=useHTML@
qu.1.1.name=Momentum of Object@
qu.1.1.question=A $ball has a momentum of $p kg&middot;m/s and a mass of $m kg.  What is its speed?@
qu.1.1.answer=$ans m/s (1 ? 0.05)@
qu.1.1.random=
		$integer\=rint(4);
		$ball\=switch($integer,"sphere","body","block","cube");
		$p\=rand(50,90,3);
		$m\=rand(2,5,3);
		$ans\=sig(3,$p/$m)@



qu.2.topic=<strong>Ch 9</strong>, <font size="-1"><b>Sec 2</b></font> - Impulse@

qu.2.1.mode=Randomized Formula@
qu.2.1.editing=useHTML@
qu.2.1.name=Ball@
qu.2.1.question=A tennis ball is thrown downward against the floor with a velocity of $v0 m/s with respect to the vertical.  The ball bounces straight up off the floor with only $percent% of its initial speed.  Find the mass of the tennis ball if the impulse delivered by the floor to the ball is $impulse kg&middot;m/s.@
qu.2.1.answer=$ans kg (1 ? 0.05)@
qu.2.1.random=
		$v0=rand(10,20,3);
		$percent\=rand(80,98,3);
		$percent1\=$percent/100;
		$impulse\=rand(-12,-5,3);
		$ans\=sig(3,-$impulse/($v0*(1+$percent1)))@



qu.3.topic=<strong>Ch 9</strong>, <font size="-1"><b>Sec 3</b></font> - Conservation of Momentum@

qu.3.1.mode=Randomized Formula@
qu.3.1.editing=useHTML@
qu.3.1.name=Bullet Hits Block@
qu.3.1.question=A bullet of mass <i>m</i> = $m_bullet g is shot in the direction of a wooden block (see Figure<span style="background:red; color:white"> <b>1</b> </span>) that is placed on a frictionless surface.  The bullet collides with the block and embeds itself into the block (see Figure<span style="background:red; color:white"> <b>2</b> </span>).  Find the speed of the $block after the collision if the initial speed of the bullet is $v0_bullet m/s and the mass of the block is $m_block kg.
<p align=center>
<img src="http://physics.unl.edu/directory/lee/edu/physics/graphics/ch9/sec3/qu1-1.gif">
</p>@
qu.3.1.answer=$ans m/s (1 ? 0.05)@
qu.3.1.random=
		$integer\=rint(2);
		$block\=switch($integer,"block","bullet");
		$v0_bullet\=rand(700,900,3);
		$m_block\=rand(1,4,3);
		$m_bullet\=rand(5,10,3);
		$ans\=sig(3,$m_bullet/1000*$v0_bullet/($m_block+$m_bullet/1000))@


qu.4.topic=<strong>Ch 9</strong>, <font size="-1"><b>Sec 4</b></font> - Inelastic Collisions@

qu.4.1.mode=Randomized Formula@
qu.4.1.editing=useHTML@
qu.4.1.name=Car Collides With Truck@
qu.4.1.question=A dump truck and a car traveling toward each other accidentally collide.  What is the speed of the car before the collision if the mass of the car is $mcar lb, the mass of the truck is $mtruck lb, the initial speed of the truck is $vtruck mi/h, and the velocity of the car-truck system after the collision is $vprime mi/h with respect to the initial direction of motion of the truck?  Consider the collision to be perfectly inelastic.  Give the answer in m/s.@
qu.4.1.answer=$ans m/s (1 ? 0.05)@
qu.4.1.random=
		$mcar\=rand(2000,4000,3);
		$mtruck\=rand(15000,25000,3);
		$mcarkg\=0.453592*$mcar;
		$mtruckkg\=0.453592*$mtruck;
		$vtruck\=rand(35,50,3);
		$k\=rand(0.3,0.5);
		$vprime\=sig(3,$vtruck*(1-$k));
		$vprimems\=1397/3125*$vprime;	
		$vtruckms\=1397/3125*$vtruck;
		$ans\=sig(3,((-$mcarkg-$mtruckkg)*$vprimems+$mtruckkg*($vtruckms))/$mcarkg)@


qu.5.topic=<strong>Ch 9</strong>, <font size="-1"><b>Sec 5</b></font> - Center of Mass@

qu.5.1.mode=Randomized Formula@
qu.5.1.editing=useHTML@
qu.5.1.name=System of 3 Masses@
qu.5.1.question=Find the <i>x</i>- coordinate of the center of mass of the system of three masses shown below if <i>x</i><sub>1</sub> = $x1 m, <i>x</i><sub>2</sub> = $x2 m, <i>m</i><sub>1</sub> = $m1 kg, <i>m</i><sub>2</sub> = $m2 kg, and <i>m</i><sub>3</sub> = $m3 kg.  Give the answer in meters, <i>m</i>.
<p align=center>
<img src="http://physics.unl.edu/directory/lee/edu/physics/graphics/ch9/sec5/qu1-1.gif">
</p>@
qu.5.1.answer=$ans m (1 ? 0.05)@
qu.5.1.random=
		$x1\=rint(1,7)+1;
		$x2\=$x1*2;
		$k_large\=rand(0.4,0.8);
		$k_small\=rand(0.15,0.45);
		$m1\=rand(2,4,3);
		$m2\=sig(3,$m1*(1+$k_large));
		$m3\=sig(3,$m1*(1+$k_large+$k_small));
		$ans\=sig(3,(($m1+$m2)*$x1+$m3*$x2)/($m1+$m2+$m3))@