Answer:
If you blow past your destination, you'll have to throw your car into this.
Which weighs more? A pound of iron or a pound of feathers?
What goes up let's of a load and come back down
If you drop me I'm sure to crack. But give me a smile and I'll always smile back.
What has no hands but might knock on your door, and if it does you better open up?
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?