A missile is fired at speed V0 at an angle 450. The missile exploded into two parts when reaches the maximum height. The part of mass m1 is thrown back at speed V1 relative to the missile speed before the explosion (V1>V0). From the shot till the explosion the wind was blown that exerts a friction force Ffriction =−kV. Exactly at the explosion the wind stops to blow. Find where the explosion accrues. Why in finding the y cordinate there is no use of the friction force? the answer says: yexplosion=V0sin45∗texplosion−0.5∗g∗t2explosion while in finding the x coordinate there is a use, didn't friction have to be taken into consideration in both coordinates? Does friction force is only horizontal and not opposite the direction of the velocity?