It depends. If you are driving and the person doesn't look like a serial killer, you should stop.
Yep that's correct
And transverse waves move perpendicular to the direction of energy transport
Answer:
the radii of curvature is 30 cm.
Explanation:
given,
object is place at = 45 cm
image appears at = 90 cm
focal length = ?
refractive index = 1.5
radii of curvature = ?


f = 30 cm
using lens formula





R = 30 cm
hence, the radii of curvature is 30 cm.
I believe you got it correct already
Answer:
3) 52500N
Explanation:
We use the mathematical definition of impulse as follows;

were F is the force experienced, t is the time of impact, m is the mass of the object and v is the velocity of impact.
Given; m = 4.5kg, v = 35m/s, t = 3 milliseconds
however, 
From equation (1);
.
Substituting all necessary values into equation (2), we obtain the following;
